Semiconductor substrate and method for manufacturing the same

ABSTRACT

A semiconductor device and a method for manufacturing thereof are provided. The method includes a step of forming a first insulating film containing silicon and oxygen as its composition over a single-crystal semiconductor substrate, a step of forming a second insulating film containing silicon and nitrogen as its composition over the first insulating film, a step of irradiating the second insulating film with first ions to form a separation layer in the single-crystal semiconductor substrate, a step of irradiating the second insulating film with second ions so that halogen is contained in the first insulating film, and a step of performing heat treatment to separate the single-crystal semiconductor substrate with a single-crystal semiconductor film left over the supporting substrate.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a semiconductor device manufacturingsubstrate which has an SOI (silicon on insulator) structure, and amethod for manufacturing the semiconductor device manufacturingsubstrate.

Note that a semiconductor device in this specification refers to alltypes of devices which can function by utilizing semiconductorcharacteristics, and electro-optic devices, semiconductor circuits, andelectronic devices are all included in the category of the semiconductordevice.

2. Description of the Related Art

With development of VLSI technology, lower power consumption and higherspeed over the scaling law which can be realized by bulk single-crystalsilicon have been demanded. In order to meet these demands, an SOIstructure has been attracting attention. This technology allows anactive region (channel formation region) of a field effect transistor(FET), which has been formed of bulk single-crystal silicon, to beformed of a single-crystal silicon thin film. It is known that a fieldeffect transistor manufactured using an SOI structure has lowerparasitic capacitance than a field effect transistor manufactured usinga bulk single-crystal silicon substrate, which is an advantage inincreasing speed.

A SIMOX substrate or a bonded substrate is known as an SOI substrate. AnSOI structure of a SIMOX substrate is obtained in such a manner thatoxygen ions are implanted into a single-crystal silicon substrate andheat treatment is performed at greater than or equal to 1300° C. to forma buried oxide film, and accordingly a single-crystal silicon film isformed on the surface. As for a SIMOX substrate, oxygen ion implantationcan be controlled precisely, and thus a single-crystal silicon film witha uniform thickness can be formed; however, there are time and costproblems because a long period of time is needed for oxygen ionimplantation. In addition, there is another problem in that asingle-crystal silicon substrate is likely to be damaged during oxygenion implantation, which has an influence on a single-crystal siliconfilm to be obtained.

An SOI structure of a bonded substrate is obtained in such a manner thattwo single-crystal silicon substrates are bonded to each other with aninsulating film interposed therebetween and one of the twosingle-crystal silicon substrates is thinned to form a single-crystalsilicon film. As a thinning method, a hydrogen ion implantationseparation method is known. A hydrogen ion implantation separationmethod is a method in which hydrogen ions are implanted into onesingle-crystal silicon substrate to form a microbubble layer at apredetermined depth from the silicon substrate surface, a thinsingle-crystal silicon film can be bonded to the other single-crystalsilicon substrate with use of the microbubble layer as a cleavage layer(see Patent Document 1: Japanese Published Patent Application No.2000-124092).

In recent years, there has been an attempt to form a single-crystalsilicon film over a substrate with an insulating surface, such as aglass substrate. For example, an SOI substrate in which a single-crystalsilicon film is formed over a glass substrate disclosed by the presentapplicant is known as an example (see Patent Document 2: JapanesePublished Patent Application No. H11-163363).

SUMMARY OF THE INVENTION

When an SOI structure is formed by a hydrogen ion implantationseparation method, structural defects such as dangling bonds occur moreeasily in a semiconductor film to be obtained because ions are directlyimplanted into a semiconductor substrate which serves as a base of thesemiconductor film. Dangling bonds might become a factor of a localizedlevel in the semiconductor film and deteriorate electric characteristicsof a semiconductor device.

In view of the above-described problems, it is an object of the presentinvention to provide a semiconductor device manufacturing substratewhich enables manufacture of a semiconductor device, electriccharacteristics of which are improved, and a method for manufacturingthe semiconductor device manufacturing substrate. It is another objectto provide a highly-reliable semiconductor device.

A semiconductor device manufacturing substrate is manufactured bytransfer of a semiconductor film separated from a semiconductorsubstrate to a supporting substrate with an insulating surface. Aninsulating film containing silicon and oxygen as its composition and aninsulating film containing silicon and nitrogen as its composition areformed in order over the semiconductor substrate which serves as a baseof the semiconductor film, and then ions are implanted into thesemiconductor substrate, whereby a separation layer is formed in aregion at a predetermined depth. Next, halogen ions are implanted intothe insulating film containing silicon and oxygen as its compositionformed over the semiconductor substrate to form an insulating filmcontaining silicon and oxygen as its composition in which halogen iscontained, and then a bonding layer is formed over the insulating filmcontaining silicon and nitrogen as its composition. The semiconductorsubstrate and the supporting substrate are superimposed on each otherand bonded to each other with the insulating film containing silicon andoxygen as its composition, the insulating film containing silicon andnitrogen as its composition, and the bonding layer from thesemiconductor substrate side interposed therebetween. Part of thesemiconductor substrate is separated at the separation layer by heattreatment and the semiconductor film is made to remain over thesupporting substrate. Accordingly, a semiconductor device manufacturingsubstrate is manufactured.

Note that “to implant ions” in this specification refers to irradiationof a semiconductor substrate with ions which are accelerated by anelectric field, so that an element of the ions used for the irradiationis introduced into the semiconductor substrate. A “separation layer” inthis specification is a region which is embrittled so as to havemicrovoids by irradiation of a semiconductor substrate with ions.Separation at a separation layer by later heat treatment enables asemiconductor layer to be formed over a supporting substrate. A “bondinglayer” in this specification refers to a film (an insulating film as atypical example) which is formed on a bonding surface which forms a bondwith a supporting substrate (or an insulating film formed over asupporting substrate).

One aspect of the present invention is a method for manufacturing asemiconductor device manufacturing substrate, which includes the stepsof forming an insulating film containing silicon and oxygen as itscomposition and an insulating film containing silicon and nitrogen asits composition in order over one surface of a single-crystalsemiconductor substrate; forming a separation layer in a region at apredetermined depth in the single-crystal semiconductor substrate byirradiation of the single-crystal semiconductor substrate with ions;irradiating the insulating film containing silicon and oxygen as itscomposition with halogen ions, so that halogen is contained in theinsulating film containing silicon and oxygen as its composition; andforming a bonding layer over the insulating film containing silicon andnitrogen as its composition, where the single-crystal semiconductorsubstrate and a supporting substrate are superimposed on each other andbonded to each other with the insulating film containing silicon andoxygen as its composition, the insulating film containing silicon andnitrogen as its composition, and the bonding layer which are stacked inorder from the single-crystal semiconductor substrate side interposedtherebetween, and part of the single-crystal semiconductor substrate isseparated at the separation layer by heat treatment at greater than orequal to 550° C. to form a single-crystal semiconductor film over thesupporting substrate.

Another aspect of the present invention is a method for manufacturing asemiconductor device manufacturing substrate, which includes the stepsof forming an insulating film containing silicon and oxygen as itscomposition and an insulating film containing silicon and nitrogen asits composition in order over one surface of a single-crystalsemiconductor substrate; forming a separation layer in a region at apredetermined depth in the single-crystal semiconductor substrate byirradiation of the single-crystal semiconductor substrate with ions;irradiating the insulating film containing silicon and oxygen as itscomposition with halogen ions, so that halogen is contained in theinsulating film containing silicon and oxygen as its composition; andforming a bonding layer over the insulating film containing silicon andnitrogen as its composition, where the single-crystal semiconductorsubstrate and a supporting substrate are superimposed on each other andbonded to each other with the insulating film containing silicon andoxygen as its composition, the insulating film containing silicon andnitrogen as its composition, and the bonding layer which are stacked inorder from the single-crystal semiconductor substrate side interposedtherebetween, and part of the single-crystal semiconductor substrate isseparated at the separation layer by heat treatment at greater than orequal to 550° C. to form a single-crystal semiconductor film over thesupporting substrate and to distribute halogen in the single-crystalsemiconductor film.

In the above-described structure, fluorine or chlorine is desirably usedas halogen.

In the above-described structure, a silicon oxide film or a siliconoxynitride film is desirably formed as the insulating film containingsilicon and oxygen as its composition. A silicon nitride film or asilicon nitride oxide film is desirably formed as the insulating filmcontaining silicon and nitrogen as its composition.

A silicon oxide film or a film which has siloxane bonds is desirablyformed as the bonding layer. The silicon oxide film which forms thebonding layer is desirably formed by a chemical vapor deposition methodwith use of organic silane or inorganic silane as a source gas.

In the above-described structure, a glass substrate, a quartz substrate,a ceramic substrate, a sapphire substrate, or a metal substrate whosesurface is coated with an insulating film can be used as the supportingsubstrate.

Another aspect of the present invention is a semiconductor devicemanufacturing substrate including a single-crystal semiconductor filmcontaining halogen which is bonded to a supporting substrate; andbetween the supporting substrate and the single-crystal semiconductorfilm, an insulating film containing silicon and oxygen as itscomposition which is in contact with the single-crystal semiconductorfilm and contains the same halogen as the single-crystal semiconductorfilm, an insulating film containing silicon and nitrogen as itscomposition which is in contact with the insulating film containingsilicon and oxygen as its composition, and a bonding layer which is incontact with the insulating film containing silicon and nitrogen as itscomposition.

In the above-described structure, halogen contained in thesingle-crystal semiconductor film and the insulating film containingsilicon and oxygen as its composition film is desirably fluorine orchlorine.

In the above-described structure, the insulating film containing siliconand oxygen as its composition is desirably a silicon oxide film or asilicon oxynitride film. The insulating film containing silicon andnitrogen as its composition is desirably a silicon nitride film or asilicon nitride oxide film. The bonding layer is desirably a siliconoxide film or a film which has siloxane bonds.

In the above-described structure, a glass substrate, a quartz substrate,a ceramic substrate, a sapphire substrate, or a metal substrate whosesurface is coated with an insulating film can be used as the supportingsubstrate.

Application of the semiconductor device manufacturing substrate of thepresent invention makes it possible to manufacture a semiconductordevice which has good electric characteristics. In addition, manufactureof a semiconductor device reliability of which is improved can berealized.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a view illustrating a structural example of a semiconductordevice manufacturing substrate;

FIGS. 2A to 2E are views illustrating an example of a method formanufacturing a semiconductor device manufacturing substrate;

FIGS. 3A to 3E are views illustrating an example of a method formanufacturing a semiconductor device manufacturing substrate;

FIGS. 4A to 4E are views illustrating an example of a method formanufacturing a semiconductor device manufacturing substrate;

FIGS. 5A to 5E are views illustrating an example of a method formanufacturing a semiconductor device manufacturing substrate;

FIGS. 6A to 6E are views illustrating an example of a method formanufacturing a semiconductor device manufacturing substrate;

FIGS. 7A to 7E are views illustrating an example of a method formanufacturing an electroluminescence display device;

FIGS. 8A to 8C are views illustrating an example of a method formanufacturing an electroluminescence display device;

FIGS. 9A and 9B are views illustrating an example of a method formanufacturing an electroluminescence display device;

FIGS. 10A and 10B are views illustrating an example of a method formanufacturing an electroluminescence display device;

FIGS. 11A to 11D are views illustrating an example of a method formanufacturing a semiconductor device;

FIGS. 12A and 12B are views each illustrating an example of a method formanufacturing a semiconductor device;

FIG. 13 is a block diagram illustrating a structure of a microprocessorobtained using a semiconductor device manufacturing substrate;

FIG. 14 is a block diagram illustrating a structure of an RFCPU obtainedusing a semiconductor device manufacturing substrate;

FIG. 15 is a view illustrating an example of bonding a semiconductorfilm to mother glass for manufacture of a display panel;

FIGS. 16A and 16B are views illustrating an example of a liquid crystaldisplay device;

FIGS. 17A and 17B are views illustrating an example of anelectroluminescence display device; and

FIGS. 18A to 18C are diagrams each illustrating an example of anelectronic device.

DETAILED DESCRIPTION OF THE INVENTION

Embodiment Modes of the present invention will be hereinafter describedwith reference to the accompanying drawings. Note that the presentinvention is not limited to the description below and it is easilyunderstood by those skilled in the art that modes and details of thepresent invention can be modified in various ways without departing fromthe purpose and scope of the present invention. Therefore, the presentinvention should not be interpreted as being limited to the descriptionbelow of Embodiment Modes. Note that, in the structures of the presentinvention described below, reference numerals denoting the same portionsmay be used in common in different drawings.

Embodiment Mode 1

A semiconductor device manufacturing substrate of this embodiment modehas an SOI structure and is formed by transfer of a semiconductor filmseparated from a semiconductor substrate to a supporting substrate. Asthe supporting substrate, a substrate which is different from asubstrate used as the semiconductor substrate is used. One mode of thesemiconductor device manufacturing substrate of this embodiment mode isshown in FIG. 1.

As for a semiconductor device manufacturing substrate 100 shown in FIG.1, a semiconductor film 140 is provided over a supporting substrate 120.An insulating film 107 containing silicon and oxygen as its compositionwhich is in contact with the semiconductor film 140, an insulating film106 containing silicon and nitrogen as its composition which is incontact with the insulating film 107 containing silicon and oxygen asits composition, and a bonding layer 114 which is in contact with theinsulating film 106 containing silicon and nitrogen as its compositionare provided between the supporting substrate 120 and the semiconductorfilm 140. That is, the semiconductor device manufacturing substrate 100has a structure in which the semiconductor film 140 is bonded to thesupporting substrate with a stacked film of the bonding layer 114, theinsulating film 106 containing silicon and nitrogen as its composition,and the insulating film 107 containing silicon and oxygen as itscomposition in order over the supporting substrate 120 interposedtherebetween.

As the semiconductor film 140, a single-crystal semiconductor or apolycrystalline semiconductor can be used and single-crystal silicon isdesirably used. In addition, a semiconductor which is capable of beingseparated from a semiconductor substrate by ion implantation separationmethod can be used as well. For example, silicon, germanium, or acompound semiconductor such as silicon germanium, gallium arsenide, orindium phosphide can be used. The semiconductor film 140 can be formedto a thickness of greater than or equal to 5 nm and less than or equalto 500 preferably greater than or equal to 10 nm and less than or equalto 200 nm.

Note that the semiconductor film 140 in this embodiment mode containshalogen. Halogen is desirably contained in the semiconductor film 140 ata peak concentration of the range of 1×10¹⁷ atoms/cm³ to 1×10²¹atoms/cm³.

A substrate with an insulating surface or a substrate with an insulatingproperty is used as the supporting substrate 120. Specifically, asubstrate which is different from a substrate used as the semiconductorsubstrate is used, and the following are given: various glass substrates(also referred to as a non-alkali glass substrate) used in theelectronics industry, such as an aluminosilicate glass substrate, analuminoborosilicate glass substrate, or a barium borosilicate glasssubstrate; a quartz substrate; a ceramic substrate; a sapphiresubstrate; a metal substrate whose surface is coated with an insulatingfilm; and the like. It is preferable to use a glass substrate used inthe electronics industry because the glass substrate is inexpensive andreduction in cost can be achieved.

A silicon oxide film or a silicon oxynitride film is formed as theinsulating film 107 containing silicon and oxygen as its composition.The insulating film 107 containing silicon and oxygen as its compositioncan be formed to a thickness of greater than or equal to 10 nm and lessthan or equal to 500 nm, preferably greater than or equal to 50 nm andless than or equal to 200 nm. Note that the insulating film 107containing silicon and oxygen as its composition contains halogen.

A silicon nitride film or a silicon nitride oxide film is formed as theinsulating film 106 containing silicon and nitrogen as its composition.The insulating film 106 containing silicon and nitrogen as itscomposition can be formed to a thickness of greater than or equal to 10nm and less than or equal to 200 nm, preferably greater than or equal to50 nm and less than or equal to 100 nm.

Note that a silicon oxynitride film in this specification means a filmwhich contains more oxygen than nitrogen and, in the case wheremeasurements are performed using Rutherford backscattering spectrometry(RBS) and hydrogen forward scattering (HFS), includes oxygen, nitrogen,silicon, and hydrogen at concentrations ranging from 50 at. % to 70 at.%, 0.5 at. % to 15 at. %, 25 at. % to 35 at. %, and 0.1 at. % to 10 at.%, respectively. In addition, a silicon nitride oxide film means a filmwhich contains more nitrogen than oxygen and, in the case wheremeasurements are performed using RBS and HFS, includes oxygen, nitrogen,silicon, and hydrogen at concentrations ranging from 5 at. % to 30 at.%, 20 at. % to 55 at. %, 25 at. % to 35 at. %, and 10 at. % to 30 at. %,respectively. Note that percentages of nitrogen, oxygen, silicon, andhydrogen fall within the ranges given above, where the total number ofatoms contained in the silicon oxynitride film or the silicon nitrideoxide film is defined as 100 at. %.

A film which has a smooth surface and can form a hydrophilic surface isdesirably formed as the bonding layer 114. For example, an insulatingfilm such as a silicon oxide film or a film which has siloxane bonds isformed as the bonding layer 114. The bonding layer 114 can be formed toa thickness of greater than or equal to 5 nm and less than or equal to500 nm, preferably greater than or equal to 10 nm and less than or equalto 100 nm.

An example of a specific manufacturing method is hereinafter describedwith reference to drawings. FIGS. 2A to 2E and FIGS. 3A to 3E arecross-sectional views illustrating an example of a method formanufacturing a semiconductor device manufacturing substrate of thisembodiment mode.

A semiconductor substrate 102 is prepared (see FIG. 2A). As thesemiconductor substrate 102, a semiconductor substrate such as a siliconsubstrate or a germanium substrate, or a compound semiconductorsubstrate such as a gallium arsenide substrate or an indium phosphidesubstrate is used. Although a single-crystal semiconductor substrate isdesirably used as the semiconductor substrate 102, a polycrystallinesemiconductor substrate can also be used. In addition, a semiconductorsubstrate to be used may be either rectangular or circular.

An insulating film 104 containing silicon and oxygen as its composition(hereinafter, also referred to a first insulating film 104 containingsilicon and oxygen as its composition) and the insulating film 106containing silicon and nitrogen as its composition are formed in orderover one surface of the semiconductor substrate 102 which has beencleaned (see FIG. 2B). These stacked films are formed on the surfaceside where the semiconductor substrate 102 forms a bond with thesupporting substrate.

The first insulating film 104 containing silicon and oxygen as itscomposition and the insulating film 106 containing silicon and nitrogenas its composition can be formed by a CVD (chemic vapor deposition)method, a sputtering method, or an ALF (atomic layer epitaxy) method.Note that a CVD method in this specification includes a plasma CVDmethod, a thermal CVD method, and a photo CVD method in its category.Alternatively, the first insulating film 104 containing silicon andoxygen as its composition can also be formed by heat treatment or plasmatreatment under an atmosphere containing oxygen, or oxidation treatmentsuch as UV ozone treatment.

A silicon oxide film or a silicon oxynitride film is formed as the firstinsulating film 104 containing silicon and oxygen as its composition.The first insulating film 104 containing silicon and oxygen as itscomposition is formed to a thickness of greater than or equal to 10 nmand less than or equal to 500 nm, preferably greater than or equal to 50nm and less than or equal to 200 nm.

A silicon nitride film or a silicon nitride oxide film is formed as theinsulating film 106 containing silicon and nitrogen as its composition.The insulating film 106 containing silicon and nitrogen as itscomposition is formed to a thickness of greater than or equal to 10 nmand less than or equal to 200 nm, preferably greater than or equal to 50nm and less than or equal to 100 nm. The insulating film 106 containingsilicon and nitrogen as its composition functions as a blocking film forpreventing metal impurities such as alkali metal or alkaline earth metalfrom diffusing toward a semiconductor film side. Thus, even when a glasssubstrate made of aluminosilicate glass or the like is used as thesupporting substrate which is to be bonded later, the insulating film106 containing silicon and nitrogen as its composition can blockdiffusion of metal impurities such as sodium contained in the glasssubstrate.

Note that, although the blocking effect can be obtained if theinsulating film 106 containing silicon and nitrogen as its compositionis formed so as to be directly in contact with the semiconductorsubstrate 102, interface characteristics might be deteriorated due toformation of trap levels. In order to prevent such a defect, the firstinsulating film 104 containing silicon and oxygen as its composition isdesirably formed between the semiconductor substrate 102 and theinsulating film 106 containing silicon and nitrogen as its composition.The first insulating film 104 containing silicon and oxygen as itscomposition and the insulating film 106 containing silicon and nitrogenas its composition are stacked from the semiconductor film 140 side,whereby improvement of electric characteristics of the interface can berealized while contamination of the semiconductor film due to metalimpurities can be prevented.

Note that the first insulating film 104 containing silicon and oxygen asits composition and the insulating film 106 containing silicon andnitrogen as its composition are desirably formed successively. This isbecause successive formation makes it possible to prevent contaminationof the interface.

Next, the semiconductor substrate 102 is irradiated with ions 108accelerated by an electric field, whereby a separation layer 112 isformed in a region at a predetermined depth in the semiconductorsubstrate 102 (see FIG. 2C). In this embodiment mode, the ions 108 areemitted from the surface side of the semiconductor substrate 102 wherethe first insulating film 104 containing silicon and oxygen as itscomposition and the insulating film 106 containing silicon and nitrogenas its composition are formed.

The depth of the semiconductor substrate 102 where the separation layer112 is formed can be controlled by the type of emitted ions 108, theacceleration voltage thereof, and the emission angle thereof. Theseparation layer 112 is formed in a region at a depth which is close tothe average penetration depth of the ions from a surface of thesemiconductor substrate 102. The depth of the semiconductor substratewhere the separation layer 112 is formed determines the thickness of asemiconductor film which is to be transferred to the supportingsubstrate later. Thus, the acceleration voltage at the time of theirradiation with the ions 108 and the dose of the ions 108 are adjustedin consideration of the thickness of the semiconductor film which is tobe transferred. It is desirable that the irradiation with the ions 108be controlled so that the semiconductor film is formed to a thickness ofgreater than or equal to 5 nm and less than or equal to 500 nm,preferably greater than or equal to 10 nm and less than or equal to 200nm.

The irradiation with the ions 108 is desirably performed using an iondoping apparatus. In other words, an ion doping method is desirably usedwhich performs irradiation with plural kinds of ions which are generatedby plasma excitation of a source gas without any mass separation beingperformed. In this embodiment mode, irradiation with ions made up of oneor a plurality of same atoms that have a single mass or ions made up ofone or a plurality of same atoms that have different masses isdesirable. Such ion doping may be performed with an acceleration voltageof greater than or equal to 10 kV and less than or equal to 100 kV,preferably greater than or equal to 30 kV and less than or equal to 80kV, at a dose of greater than or equal to 1×10¹⁶ ions/cm² and less thanor equal to 4×10¹⁶ ions/cm², and with a beam current density of greaterthan or equal to 2 μA/cm², preferably greater than or equal to 5 μA/cm²,further preferably greater than or equal to 10 μA/cm².

As the ions 108, ions made up of one or a plurality of same atoms thathave a single mass or ions made up of one or a plurality of same atomsthat have different masses generated by plasma excitation of a sourcegas selected from hydrogen and deuterium are desirably emitted. Whenirradiation with hydrogen ions is performed, it is desirable that theions of hydrogen include H⁺ ions, H₂ ⁺ ions, and H₃ ⁺ ions with a highproportion of H₃ ⁺ ions because ion irradiation efficiency can beincreased and irradiation time can be shortened. Accordingly, a regionof the semiconductor substrate 102 where the separation layer 112 isformed can be made to contain hydrogen at greater than or equal to1×10²⁰ atoms/cm³ (preferably, 1×10²¹ atoms/cm³). When ahigh-concentration hydrogen-doped region is locally formed in thesemiconductor substrate 102, a crystal structure is disordered andmicrovoids are formed, whereby the separation layer 112 can be made tohave a porous structure. In this case, by heat treatment at relativelylow temperature, a change occurs in the volume of the microvoids formedin the separation layer 112. Then, cleavage is performed along theseparation layer 112, whereby a thin semiconductor film can be formed.

Note that the separation layer 112 can be formed in a similar mannereven if the semiconductor substrate 102 can be irradiated with aspecific type of ions with mass separation being performed. Also in thiscase, selective irradiation with ions which have large mass is desirablebecause an effect which is similar to the above-described effect can beobtained.

Note that there is the case where the ions 108 are implanted at a highdose in order to form the separation layer 112 at a predetermined depth.In this embodiment mode, the semiconductor substrate 102 is irradiatedwith the ions 108 through the stacked film of the first insulating film104 containing silicon and oxygen as its composition and the insulatingfilm 106 containing silicon and nitrogen as its composition which areformed over the semiconductor substrate 102, and thus roughness of thesurface of the semiconductor substrate 102 due to introduction of ionscan be prevented.

Next, the first insulating film 104 containing silicon and oxygen as itscomposition is irradiated with halogen ions 113 accelerated by anelectric field, whereby an insulating film 105 containing silicon andoxygen as its composition (hereinafter, referred to as a secondinsulating film 105 containing silicon and oxygen as its composition) isobtained which is the first insulating film 104 containing silicon andoxygen as its composition in which halogen is contained (see FIG. 2D).

The first insulating film 104 containing silicon and oxygen as itscomposition is irradiated with the halogen ions 113 which have passedthrough the insulating film 106 containing silicon and nitrogen as itscomposition, whereby a halogen element which forms the halogen ions 113are introduced into the first insulating film 104 containing silicon andoxygen as its composition. The depth to which the halogen ions 113 areintroduced can be controlled by the type of halogen ions 113, theacceleration voltage thereof, and the emission angle thereof.

The irradiation with the halogen ions 113 can be performed using an iondoping apparatus or an ion irradiation apparatus. In other words, an iondoping method can be desirably used which performs irradiation withplural kinds of ions without any mass separation being performed, or anion irradiation method can be used which performs irradiation with aspecific type of ion with mass separation being performed. For example,the first insulating film 104 containing silicon and oxygen as itscomposition can be irradiated with the halogen ions 113 at anacceleration voltage of greater than or equal to 30 kV and less than orequal to 100 kV and at a dose of greater than or equal to 1×10¹⁴ions/cm² and less than or equal to 1×10¹⁶ ions/cm².

A halogen element such as fluorine or chlorine may be ionized as thehalogen ions 113, and fluorine is preferably used. Although halogen canbe uniformly distributed in the second insulating film 105 containingsilicon and oxygen as its composition, in many cases, distribution isperformed in accordance with the Gaussian distribution when irradiationwith ions are performed. That is, a high-concentration region of halogenis formed at a predetermined depth in the second insulating film 105containing silicon and oxygen as its composition, and the halogen iswidely distributed according to the concentration of thehigh-concentration region as a peak concentration. Here, halogen isdesirably contained in the second insulating film 105 containing siliconand oxygen as its composition at a peak concentration of the range of1×10¹⁹ atoms/cm³ to 1×10²¹ atoms/cm³.

Next, the bonding layer 114 is formed over the insulating film 106containing silicon and nitrogen as its composition (see FIG. 2E and FIG.3A).

A film which has a smooth surface and can form a hydrophilic surface isdesirably formed as the bonding layer 114. An insulating film formed bychemical reaction is desirably used as such a bonding layer 114. Forexample, an insulating film formed by thermal reaction or chemicalreaction is suitable. This is because an insulating film which is formedby chemical reaction easily obtains the smoothness of its surface. Thebonding layer 114 which has a smooth surface and forms a hydrophilicsurface is desirably formed to a thickness of greater than or equal to 5nm and less than or equal to 500 nm, preferably greater than or equal to10 nm and less than or equal to 100 nm. The bonding layer 114 is formedto a thickness of the above-described range, whereby it is possible tosmooth roughness of a surface over which a film is to be formed and alsoto ensure smoothness of a growing surface of the film.

As the bonding layer 114 which satisfies such conditions, a siliconoxide film formed by a CVD method with use of organic silane as a sourcegas is desirably used. As organic silane, the following can be used: asilicon-containing compound such as tetraethoxysilane (TEOS) (chemicalformula: Si(OC₂H₅)₄), tetramethylsilane (TMS) (chemical formula:Si(CH₃)₄), trimethylsilane (chemical formula: (CH₃)₃SiH),tetramethylcyclotetrasiloxane (TMCTS), octamethylcyclotetrasiloxane(OMCTS), hexamethyldisilazane (HMDS), triethoxysilane (chemical formula:SiH(OC₂H₅)₃), and trisdimethylaminosilane (chemical formula:SiH(N(CH₃)₂)₃). Note that, when a silicon oxide film is formed by a CVDmethod with use of organic silane as a source gas, a gas impartingoxygen is desirably mixed. Oxygen, nitrous oxide, nitrogen dioxide, orthe like can be used as a gas imparting oxygen. In addition, an inertgas such as argon, helium, or nitrogen or a hydrogen gas may be mixed.Alternatively, a silicon oxide film formed by a CVD method with use ofinorganic silane such as monosilane, disilane, or trisilane as a sourcegas can also be used as the bonding layer 114. Also in this case, a gasimparting oxygen, an inert gas, or the like is desirably mixed. Notethat the bonding layer 114 is desirably formed at a temperature which islower than the temperature of the heat treatment performed later forseparating the semiconductor film from the semiconductor substrate suchas a single-crystal semiconductor substrate or a polycrystallinesemiconductor substrate. For example, the bonding layer 114 is formed ata temperature of less than or equal to 350° C.

Further alternatively, a film having siloxane (Si—O—Si) bonds can alsobe used as the bonding layer 114. Note that a film which has siloxanebonds in this specification refers to a film in which a bond of silicon(Si) and oxygen (O) is included and a skeleton structure is formed bythe bond of silicon and oxygen. Siloxane has a substituent. An organicgroup containing at least hydrogen (e.g., an alkyl group or an aromatichydrocarbon) is given as a substituent. Alternatively, a fluoro groupmay be used. Further alternatively, a fluoro group and an organic groupcontaining at least hydrogen may be used. Note that a film which hassiloxane bonds can be formed by an application method such as a spincoating method.

The supporting substrate 120 is prepared (see FIG. 3B). As describedabove, a substrate with an insulating surface or a substrate with aninsulating property is used as the supporting substrate 120.Specifically, the following are given: various glass substrates used inthe electronics industry, such as an aluminosilicate glass substrate, analuminoborosilicate glass substrate, or a barium borosilicate glasssubstrate; a quartz substrate, a ceramic substrate; a sapphiresubstrate; a metal substrate whose surface is coated with an insulatingfilm; and the like.

The semiconductor substrate 102 and the supporting substrate 120 aresuperimposed on each other and bonded to each other with the secondinsulating film 105 containing silicon and oxygen as its composition,the insulating film 106 containing silicon and nitrogen as itscomposition, and the bonding layer 114 which are stacked in order overthe semiconductor substrate 102 interposed therebetween (see FIG. 3C).

Surfaces of the semiconductor substrate 102 and the supporting substrate120 which form a bond are sufficiently cleaned in advance. Then, thesupporting substrate 120 and the bonding layer 114 which is the toplayer of the stacked films formed over the semiconductor substrate 102are disposed in contact with each other, whereby a bond is formed. It isconsidered that Van der Wags force acts on the bonding at an early stageand a strong bond can be formed by a hydrogen bond which is formed bypressure bonding of the supporting substrate 120 and the semiconductorsubstrate 102.

Note that heat treatment or pressure treatment is desirably performedafter the supporting substrate 120 and the semiconductor substrate 102are bonded to each other. Heat treatment or pressure treatment makes itpossible to increase the bond strength. Heat treatment is performed at atemperature which is less than or equal to the heat resistancetemperature of the supporting substrate 120 and also does not exceed thetemperature of the heat treatment for separating the semiconductorsubstrate, which is performed later. Pressure treatment is performed sothat pressure is applied in a direction perpendicular to the bondingsurface and in consideration of the pressure resistance of thesupporting substrate 120 and the semiconductor substrate 102.

In addition, in order to form a good bond between the semiconductorsubstrate 102 and the supporting substrate 120, one or both of thebonding surfaces may be activated before the supporting substrate 120and the semiconductor substrate 102 are disposed in contact with eachother. For example, the bonding surface can be activated by irradiationwith an atomic beam or an ion beam, specifically, an atomic beam of aninert gas such as argon or an ion beam thereof. Alternatively, thebonding surface can be activated by radical treatment. Such surfaceactivation treatment makes it possible to increase the bond strengthbetween different materials. Alternatively, one or both of the bondingsurfaces may be cleaned with ozone-containing water, oxygen-containingwater, hydrogen-containing water, pure water, or the like. Treatment formaking the bonding surface hydrophilic is added in this manner, wherebyan OH group of the bonding surface can be increased. As a result, bondby a hydrogen bond can be further strengthened.

Next, heat treatment is performed, whereby part of the semiconductorsubstrate 102 is separated at the separation layer 112. Thesemiconductor substrate 102 is bonded to the supporting substrate 120with the insulating films interposed therebetween and part of thesemiconductor substrate 102 is separated at the separation layer 112;accordingly, the semiconductor film 140 remains over the supportingsubstrate 120 (see FIG. 3D).

Heat treatment is desirably performed at a temperature of greater thanor equal to the deposition temperature of the bonding layer 114 and lessthan or equal to the strain point of the supporting substrate 120. Bythe heat treatment, a change occurs in the volume of the microvoidsformed in the separation layer 112, and the semiconductor substrate 102can be cleaved along the separation layer 112. A state is obtained inwhich the bonding layer 114 formed over the semiconductor substrate 102is bonded to the supporting substrate 120 and the semiconductor film 140with the same crystallinity as the semiconductor substrate 102 remainsover the supporting substrate 120. For example, a single-crystal siliconsubstrate is used as the semiconductor substrate 102 and a glasssubstrate is used as the supporting substrate 120, whereby asingle-crystal silicon film can be formed over the glass substrate withthe insulating films interposed therebetween. Note that, when a glasssubstrate is used as the supporting substrate 120, heat treatment isdesirably performed at a temperature of less than or equal to 650° C.

Note that at the time of the heat treatment shown in FIG. 3D, by heattreatment at desirably greater than or equal to 550° C. for 30 minutesor more, halogen contained in the second insulating film 105 containingsilicon and oxygen as its composition is distributed again and diffusedtoward the semiconductor film 140 (the semiconductor substrate 102)side. In this embodiment mode, the semiconductor film 140 is formed insuch a manner that the semiconductor substrate 102 is separated byembrittlement and heat treatment by irradiation with ions generatedusing hydrogen as a source gas, and a large number of dangling bonds areformed at the separation surface (a region which serves as a cleavagesurface) at which the semiconductor film 140 is separated and in thesemiconductor film 140. In addition, dangling bonds are also formed atan interface with the second insulating film 105 containing silicon andoxygen as its composition which is under the semiconductor film 140 dueto interruption of a bond between atoms at the interface. Halogendiffused from the second insulating film 105 containing silicon andoxygen as its composition has a function of terminating dangling bondsat the separation surface of the semiconductor film 140, in thesemiconductor film 140, and at the interface between the semiconductorfilm 140 and the second insulating film 105 containing silicon andoxygen as its composition. For example, when the semiconductor film 140is a silicon film and the second insulating film 105 containing siliconand oxygen as its composition contains fluorine, Si—F bonds aregenerated in regions where dangling bonds are terminated.

Halogen is contained in the semiconductor film 140 terminated byhalogen. The amount of halogen contained in the semiconductor film 140depends on the amount of generated dangling bonds in the semiconductorfilm 140 and the relationship between the temperature of the heattreatment for separating the semiconductor substrate and the diffusioncoefficient of halogen contained in the second insulating film 105containing silicon and oxygen as its composition. Halogen is desirablycontained in the semiconductor film 140 at a peak concentration of therange of 1×10¹⁷ atoms/cm³ to 1×10²¹ atoms/cm³. Note that halogencontained in the semiconductor film 140 is uniformly distributed in somecases or has a local peak concentration and is distributed after beingdiffused from a region having the peak concentration in some cases. Inaddition, in some cases, since halogen contained in the semiconductorfilm 140 (the semiconductor substrate 102 before separation at theseparation layer 112) is diffused from the second insulating film 105containing silicon and oxygen as its composition which is in contactwith the semiconductor film 140, the halogen has a peak concentration inthe vicinity of the interface with the second insulating film 105containing silicon and oxygen as its composition, and the halogen isdistributed so that the concentration is decreased from the vicinity ofthe interface to the separation surface of the semiconductor film 140.

Here, a halogen element, especially fluorine, has highelectronegativity. Thus, the bond energy is higher and a stablestructure is formed more easily in the case where a halogen elementforms a bond with one element, compared with the case where an elementother than the halogen element forms a bond with the one element. Forexample, although it is known that a semiconductor film such as asilicon film is terminated by hydrogen, hydrogen is easily desorbed fromsilicon by heat treatment performed at about 400° C. On the other hand,halogen typified by fluorine has higher bond energy with silicon thanhydrogen, and thus halogen can exist more stably than hydrogen. Thus,halogen is diffused in a semiconductor film or at an interface thereof,whereby effective termination of dangling bonds can be realized. Thatis, the heat treatment shown in FIG. 3D is performed at greater than orequal to 550° C. and less than or equal to the strain point of thesupporting substrate 120, and at greater than or equal to 550° C. andless than or equal to 650° C. when a glass substrate is used as thesupporting substrate 120, whereby the semiconductor substrate 102 can beseparated at the separation layer 112 and also termination of danglingbonds in the obtained semiconductor film 140 can be realized.

Alternatively, dangling bonds can be terminated in such a manner thathalogen is directly introduced into the semiconductor substrate or thesemiconductor film. However, direct introduction of halogen causesgreater damage to the semiconductor substrate or the semiconductor film.Thus, halogen which is contained in an insulating film (here, the secondinsulating film 105 containing silicon and oxygen as its composition) inadvance is distributed again, whereby termination of dangling bonds canbe realized while damage to the semiconductor film can be suppressed.

A dangling bond is a structural defect and might cause adverse effectssuch as deterioration of semiconductor characteristics if it exists in asemiconductor film or at an interface thereof. Therefore, termination byhalogen makes it possible to improve semiconductor characteristics andrealize manufacture of a semiconductor device which has good electriccharacteristics.

In addition, by heat treatment, halogen contained in the secondinsulating film 105 containing silicon and oxygen as its composition isdistributed again to be diffused toward the semiconductor film 140 (thesemiconductor substrate 102) side, and thus the amount of halogencontained in the second insulating film 105 containing silicon andoxygen as its composition is decreased. That is, after the heattreatment, an insulating film 107 containing silicon and oxygen as itscomposition (hereinafter, referred to as a third insulating film 107containing silicon and oxygen as its composition) is obtained which isthe second insulating film 105 containing silicon and oxygen as itscomposition in which the amount of contained halogen is decreased.

Note that halogen is contained in the third insulating film 107containing silicon and oxygen as its composition, whereby a getteringeffect of metal impurities and a blocking effect thereof can beobtained. Thus, contamination of the semiconductor film 140 due to metalimpurities can be prevented.

In addition, by heat treatment for separating the semiconductorsubstrate 102, the bond strength at a bonding surface of the supportingsubstrate 120 and the semiconductor substrate 102 can be increased.Moreover, heat treatment for increasing the bond strength may beperformed before the heat treatment for separating the semiconductorsubstrate 102 so that heat treatment of two or more stages is performed.For example, after heat treatment is performed at a temperature ofgreater than or equal to 200° C. and less than or equal to 400° C.,another heat treatment may be performed at a temperature of greater thanor equal to 550° C.

By the separation of the semiconductor substrate 102, a semiconductordevice manufacturing substrate which has an SOI structure in which thesemiconductor film 140 is bonded to the supporting substrate 120 withthe bonding layer 114, the insulating film 106 containing silicon andnitrogen as its composition, and the third insulating film 107containing silicon and oxygen as its composition interposed therebetweenis manufactured. The semiconductor film 140 and the interface thereofare terminated by halogen when heat treatment for separating thesemiconductor substrate 102 is performed. In addition, the insulatingfilm 106 containing silicon and nitrogen as its composition which has ahigh blocking effect is formed between the semiconductor film 140 andthe supporting substrate 120. Thus, a semiconductor device which hasgood electric characteristics and high reliability can be manufacturedwith use of the semiconductor device manufacturing substrate obtained inthis embodiment mode.

Note that flatness of the surface of the semiconductor film 140 which istransferred to the supporting substrate 120 is damaged due to theirradiation step with ions and the separation step, and the surface isuneven. The separation layer 112 remains on the surface of thesemiconductor film 140 in some cases. If the surface of thesemiconductor film 140 is uneven, it becomes difficult to form a thingate insulating film with excellent withstand voltage when forming asemiconductor device with use of the obtained semiconductor devicemanufacturing substrate. Therefore, it is desirable to performplanarization treatment on the semiconductor film 140 (see FIG. 3E).

For example, as the planarization treatment, chemical mechanicalpolishing (CMP) is desirably performed on the semiconductor film 140.Alternatively, the semiconductor film 140 may be planarized byirradiation with a laser beam or heat treatment with an electricfurnace, a lamp annealing furnace, a rapid thermal annealing (RTA)apparatus, or the like. Further alternatively, the semiconductor film140 may be planarized by a combination of CMP treatment and irradiationwith a laser beam or heat treatment. Note that not only canplanarization of the semiconductor film be realized but also crystaldefects, damages, or the like can be repaired by irradiation of thesemiconductor film 140 with a laser beam or heat treatment performed onthe semiconductor film 140. In addition, a damaged layer of the surfacedue to CMP treatment can be repaired by irradiation with a laser beam orheat treatment after CMP treatment. Furthermore, CMP treatment or thelike may be performed for the purpose of thinning the obtainedsemiconductor film.

Note that the semiconductor film is desirably irradiated with a laserbeam under a nitrogen atmosphere with an oxygen concentration of lessthan or equal to 10 ppm. This is because the surface of thesemiconductor film might get rough if irradiation with a laser beam isperformed under an oxygen atmosphere. In addition, it is desirable thatafter the semiconductor film is irradiated with a laser beam, heattreatment be performed again at greater than or equal to 550° C. toagain diffuse halogen contained in the insulating film containingsilicon and oxygen as its composition which is under the semiconductorfilm. This is because, in some cases, halogen which terminates danglingbonds in the semiconductor film is desorbed if the semiconductor film isirradiated with a laser beam. Note that heat treatment of thesemiconductor film is performed in order to terminate dangling bondswhich are generated again due to desorption of halogen, and thus it isdesirable that heat treatment of the semiconductor film be performedusing the temperature of the heat treatment for separating thesemiconductor substrate at the separation layer as an upper limit.

A variety of semiconductor devices can be manufactured with use of thesemiconductor device manufacturing substrate which is manufactured asdescribed above.

Note that, although the example in which the area of the supportingsubstrate 120 is bigger than that of the semiconductor substrate 102 isdescribed with reference to drawings in this embodiment mode, thepresent invention is not particularly limited thereto. As the supportingsubstrate 120, a substrate with approximately the same area as thesemiconductor substrate 102 may be used. Alternatively, a substrate witha different shape from the semiconductor substrate 102 may be used asthe supporting substrate 120.

In addition, the semiconductor substrate 102 from which thesemiconductor film 140 has been separated can be reused. That is, thesemiconductor substrate 102 separated as shown in FIG. 3D can be reusedas the semiconductor substrate 102 shown in FIG. 2A. Note that it isdesirable that the separation surface of the semiconductor film 140 (theseparation layer 112 serving as a cleavage surface) be planarized whenthe semiconductor substrate 102 is reused. The planarization treatmenthere may be performed in a similar manner to the above-describedplanarization of the semiconductor film 140, and CMP treatment,irradiation with a laser beam, heat treatment, or the like may be usedas appropriate. In addition, planarization or repair of crystal defectsmay be performed with a combination of some kinds of treatment. Thesemiconductor substrate which serves as a base is reused whenmanufacturing the semiconductor device manufacturing substrate, wherebydrastic cost reduction can be realized. Needless to say, thesemiconductor substrate 102 from which the semiconductor film 140 hasbeen separated may also be used for purposes other than manufacture ofthe semiconductor device manufacturing substrate.

Note that a bonding layer may also be provided on the supportingsubstrate 120 side. An example of a method for manufacturing asemiconductor device manufacturing substrate in which a bonding layer isprovided on the supporting substrate 120 side is described withreference to FIGS. 4A to 4E.

The semiconductor substrate 102 is prepared, and the first insulatingfilm containing silicon and oxygen as its composition and the insulatingfilm 106 containing silicon and nitrogen as its composition are stackedin order over one of surfaces of the cleaned semiconductor substrate102. Irradiation with ions which are obtained by ionization of hydrogenor deuterium is performed from the side of the semiconductor substrate102, where the first insulating film containing silicon and oxygen asits composition and the insulating film 106 containing silicon andnitrogen as its composition are formed, whereby the separation layer 112is formed at a predetermined depth in the semiconductor substrate 102.Next, halogen ions are made to pass through the insulating film 106containing silicon and nitrogen as its composition and the firstinsulating film containing silicon and oxygen as its composition isirradiated with the halogen ions, whereby the second insulating film 105containing silicon and oxygen as its composition is obtained. Then, thebonding layer 114 is formed over the insulating film 106 containingsilicon and nitrogen as its composition (see FIG. 4A). Note that thedescription of FIG. 4A follows the descriptions of FIGS. 2A to 2E.

The supporting substrate 120 is prepared. Then, a bonding layer 124 isformed over the supporting substrate 120 (see FIG. 4B). Here, an examplein which the bonding layer 124 is formed over the supporting substrate120 with a barrier film 122 interposed therebetween is described.

As described above, a substrate with an insulating surface or asubstrate with an insulating property is used as the supportingsubstrate 120. Specifically, the following are given: various glasssubstrates used in the electronics industry, such as an aluminosilicateglass substrate, an aluminoborosilicate glass substrate, or a bariumborosilicate glass substrate; a quartz substrate; a ceramic substrate; asapphire substrate; a metal substrate whose surface is coated with aninsulating film; and the like.

A film which has a smooth surface and can form a hydrophilic surface,which is similar to the film used as the bonding layer 114 is desirablyformed as the bonding layer 124. For example, a silicon oxide film whichis formed by a CVD method using organic silane such as ThOS, orinorganic silane such as monosilane as a source gas; a film which hassiloxane bonds; or the like can be used.

The deposition temperature of the bonding layer 124 is needed to be lessthan or equal to the strain point of the supporting substrate 120. Forexample, when a glass substrate is used as the supporting substrate 120,the deposition temperature of the bonding layer 124 is desirably lessthan or equal to the strain point of glass, preferably less than orequal to 650° C.

Note that, when a glass substrate used in the electronics industry, suchas an aluminosilicate glass substrate, an aluminoborosilicate glasssubstrate, or a barium borosilicate glass substrate is used as thesupporting substrate 120, the cost of the substrate is inexpensive andcost reduction can be achieved. However, a small amount of metalimpurities, for example, alkali metal such as sodium or alkaline earthmetal is contained in the glass substrate, and the metal impurities arediffused from the supporting substrate to the semiconductor film andmight have an adverse effect on the characteristics of a semiconductordevice to be manufactured. As described above, a blocking effect ofmetal impurities is obtained by the insulating film 106 containingsilicon and nitrogen as its composition provided on the semiconductorsubstrate 102 side, and the blocking effect can be increased byprovision of another barrier film 122 which is capable of blocking metalimpurities on the supporting substrate 120 side. The barrier film 122can be formed as a single-layer film or a stacked-layer film and can beformed to a thickness of greater than or equal to 10 nm and less than orequal to 400 nm. The barrier film 122 includes at least one layer whichhas a high effect of blocking metal impurities such as alkali metal oralkaline earth metal. As such a film, there are a silicon nitride film,a silicon nitride oxide film, an aluminum nitride film, and the like.

For example, when the barrier film 122 is formed as a single-layer film,a silicon nitride film, a silicon nitride oxide film, or an aluminumnitride film can be formed to a thickness of greater than or equal to 10nm and less than or equal to 200 nm. When the barrier film 122 is formedas two-layer stacked structure, for example, a stacked film of a siliconnitride film and a silicon oxide film; a stacked film of a siliconnitride film and a silicon oxynitride film; a stacked film of siliconnitride oxide film and a silicon oxide film; or a stacked film of asilicon nitride oxide film and a silicon oxynitride film can be formed.Note that, as for the two-layer films which are exemplified, the firstmentioned film is preferably formed over the supporting substrate 120.This is because a film with a higher blocking effect is formed as alower layer (on the supporting substrate 120 side) and a film whichreduces the internal stress of the lower layer is formed as an upperlayer (on the bonding layer 124 side) in the two-layer barrier film 122so that the semiconductor film is not affected by the internal stress ofthe barrier film 122.

The semiconductor substrate 102 and the supporting substrate 120 aresuperimposed on each other and bonded to each other with the secondinsulating film 105 containing silicon and oxygen as its composition,the insulating film 106 containing silicon and nitrogen as itscomposition, and the bonding layer 114 which are stacked in order overthe semiconductor substrate 102 interposed therebetween and also withthe barrier film 122 and the bonding layer 124 which are stacked inorder over the supporting substrate 120 interposed therebetween (seeFIG. 4C).

Here, the bonding layer 124 formed over the supporting substrate 120 andthe bonding layer 114 formed over the semiconductor substrate 102 aremade to face each other to be disposed in contact with each other,whereby a bond is formed. Note that the bonding surfaces which form thebond are sufficiently cleaned in advance. A strong bond by a hydrogenbond can be formed by pressure bonding of the supporting substrate 120and the semiconductor substrate 102. A structure in which the bondinglayer 114 and the bonding layer 124 are bonded to each other makes itpossible to increase the bond strength between the bonding layers 114and 124. Note that, in order to form a good bond between the supportingsubstrate 120 and the semiconductor substrate 102, activation (includinghydrophilization) of one or both of the bonding surfaces of the bondinglayer 114 and the bonding layer 124 may be performed. Heat treatment orpressure treatment performed after bonding the supporting substrate 120and the semiconductor substrate 102 makes it possible to increase thebond strength. Note that when heat treatment is performed, thetemperature is set so as not to exceed the temperature of the heattreatment for separating the semiconductor substrate, which is performedlater.

Heat treatment is performed to separate part of the semiconductorsubstrate 102 at the separation layer 112, whereby an SOT structure inwhich the semiconductor film 140 is bonded to the supporting substrate120 is obtained (see FIG. 4D). Planarization treatment is desirablyperformed on the semiconductor film 140 (see FIG. 4E). The descriptionsof FIGS. 4D and 4E follow the descriptions of FIGS. 3D and 3E,respectively.

By the heat treatment shown in FIG. 4D, halogen contained in the secondinsulating film 105 containing silicon and oxygen as its composition isdistributed again and diffused to the semiconductor film 140 (thesemiconductor substrate 102) side. As a result, dangling bonds at theseparation surface of the semiconductor film 140, in the semiconductorfilm 140, and at an interface between the semiconductor film 140 and theinsulating film containing silicon and oxygen as its composition areterminated. For example, when the semiconductor film 140 is a siliconfilm and the second insulating film 105 containing silicon and oxygen asits composition contains fluorine, Si—F bonds are generated in regionswhere dangling bonds are terminated.

Note that, since halogen is diffused from the second insulating film 105containing silicon and oxygen as its composition to the semiconductorfilm 140 by the heat treatment, the amount of halogen contained in thesecond insulating film 105 containing silicon and oxygen as itscomposition is decreased. Thus, after the heat treatment, a thirdinsulating film 107 containing silicon and oxygen as its composition isobtained which is the second insulating film 105 containing silicon andoxygen as its composition in which the amount of halogen is decreased.Note that halogen is contained in the third insulating film 107containing silicon and oxygen as its composition, whereby a getteringeffect of metal impurities can be expected.

The semiconductor film 140 is terminated by halogen, and halogen iscontained in the semiconductor film 140. The amount of halogen containedin the semiconductor film 140 depends on the amount of dangling bonds inthe semiconductor film 140 and the relationship between the temperatureof the heat treatment and the diffusion coefficient of halogen. Here,halogen is desirably contained in the semiconductor film 140 at a peakconcentration of greater than or equal to 1×10¹⁷ atoms/cm³ and less thanor equal to 1×10²¹ atoms/cm³.

Through the above-described steps, the semiconductor devicemanufacturing substrate 100 can be manufactured in which thesemiconductor film 140 is bonded to the supporting substrate 120 withthe barrier film 122, the bonding layer 124, the bonding layer 114, theinsulating film 106 containing silicon and nitrogen as its composition,and the third insulating film 107 containing silicon and oxygen as itscomposition which are stacked in order over the supporting substrate 120interposed therebetween.

Alternatively, the silicon oxide film provided over the semiconductorsubstrate 102 can be formed of a thermal oxide film. Hereinafter, thedescription is made on the case with reference to FIGS. 5A to 5E andFIGS. 6A to 6E.

The semiconductor substrate 102 is prepared, and the cleanedsemiconductor substrate 102 is thermally oxidized, whereby a thermaloxide film 103 (hereinafter, referred to as a first thermal oxide film103) is formed (see FIG. 5A).

As the semiconductor substrate 102, for example, a semiconductorsubstrate such as a silicon substrate or a germanium substrate, and acompound semiconductor substrate such as a gallium arsenide substrate oran indium phosphide substrate are given. Here, a single-crystal siliconsubstrate is used.

For thermal oxidation, wet oxidation may be performed, and dry oxidationis preferably performed. For example, thermal oxidation may be performedunder an oxygen atmosphere at a temperature of greater than or equal to800° C. and less than or equal to 1200° C., preferably at greater thanor equal to 1000° C. and less than or equal to 1100° C. Although thethickness of the first thermal oxide film 103 may be determined asappropriate by a practitioner, the first thermal oxide film 103 isformed to a thickness of greater than or equal to 10 nm and less than orequal to 500 nm, preferably greater than or equal to 50 nm and less thanor equal to 200 nm. The thickness of the first thermal oxide film 103can be controlled by a treatment atmosphere, processing time, or thelike. Note that the thickness of the semiconductor substrate 102 isreduced in some cases because the semiconductor substrate 102 isthermally oxidized. Here, a single-crystal silicon substrate is used asthe semiconductor substrate 102, and a silicon oxide film is formed asthe first thermal oxide film 103.

The insulating film 106 containing silicon and nitrogen as itscomposition is formed over one of surfaces of the semiconductorsubstrate 102, where the first thermal oxide film 103 is formed (seeFIG. 5B). Irradiation with ions 108 which are obtained by ionization ofhydrogen or deuterium is performed from the side of the semiconductorsubstrate 102, where the insulating film 106 containing silicon andnitrogen as its composition is formed with the first thermal oxide film103 interposed therebetween, whereby the separation layer 112 is formedat a predetermined depth in the semiconductor substrate 102 (see FIG.5C). The descriptions of FIGS. 5B and 5C follow the descriptions ofFIGS. 2B and 2C, respectively.

Next, the halogen ions 113 are made to pass through the insulating film106 containing silicon and nitrogen as its composition and the firstthermal oxide film 103 is irradiated with the halogen ions 113, wherebya thermal oxide film 153 (hereinafter, referred to as a second thermaloxide film 153) containing halogen is obtained.

The first thermal oxide film 103 is desirably irradiated with thehalogen ions 113 under the following conditions: an acceleration voltageof greater than or equal to 30 kV and less than or equal to 100 kV, adose of approximately greater than or equal to 1×10¹⁴ ions/cm² and lessthan or equal to 1×10¹⁶ ions/cm². Irradiation is performed under suchconditions, whereby halogen can be contained in the second thermal oxidefilm 153 at a peak concentration of the range of 1×10¹⁹ atoms/cm³ to1×10²¹ atoms/cm³. In addition, halogen is contained in the secondthermal oxide film 153 in accordance with a Gaussian distribution.

Next, the bonding layer 114 is formed over the insulating film 106containing silicon and nitrogen as its composition (see FIG. 5E and FIG.6A). A film which has a smooth surface and can form a hydrophilicsurface is desirably formed as the bonding layer 114. For example, asilicon oxide film or a film which has siloxane bonds may be formed asthe bonding layer 114. The detailed description thereof follows thedescription of FIG. 2E.

The supporting substrate 120 is prepared (see FIG. 6B). As thesupporting substrate 120, the following are given: various glasssubstrates used in the electronics industry, such as an aluminosilicateglass substrate, an aluminoborosilicate glass substrate, or a bariumborosilicate glass substrate; a quartz substrate; a ceramic substrate; asapphire substrate; a metal substrate whose surface is coated with aninsulating film; and the like. Here, a glass substrate is used.

The supporting substrate 120 and the semiconductor substrate 102 aresuperimposed on each other and bonded to each other with the secondthermal oxide film 153, the insulating film 106 containing silicon andnitrogen as its composition, and the bonding layer 114 which are formedover the semiconductor substrate 102 interposed therebetween (see FIG.6C).

Here, the supporting substrate 120 and the bonding layer 114 formed overthe semiconductor substrate 102 are made to face each other to bedisposed in contact with each other, whereby a bond is formed. Note thatthe bonding surfaces which form the bond are sufficiently cleaned. Astrong bond by a hydrogen bond can be formed by pressure bonding of thesupporting substrate 120 and the semiconductor substrate 102.

Note that activation (including hydrophilization) of one or both of thebonding surfaces may be performed in order to increase the bond strengthbetween the supporting substrate 120 and the semiconductor substrate102. For an activation method of the bonding surface, there areirradiation with an atomic beam with use of an inert gas or irradiationwith an ion beam with use of an inert gas, radical treatment, cleaningtreatment with ozone water or the like, and the like. Heat treatment orpressure treatment performed after bonding the supporting substrate 120and the semiconductor substrate 102 makes it possible to increase thebond strength. Note that when heat treatment is performed, thetemperature is set so as not to exceed the temperature for heattreatment for separating the semiconductor substrate, which is performedlater.

Next, heat treatment is performed to separate part of the semiconductorsubstrate 102 at the separation layer 112. The semiconductor substrate102 is bonded to the supporting substrate 120 with the insulating filminterposed therebetween. Thus, the semiconductor film 140 can remainover the supporting substrate 120 by separation of part of thesemiconductor substrate 102, whereby an SOI structure is obtained inwhich the semiconductor film 140 is bonded to the supporting substrate120 (see FIG. 6D). Note that the flatness of the separation surface ofthe semiconductor film 140 is damaged, and also a separation layerformed by irradiation with hydrogen ions or deuterium ions remains.Thus, CMP treatment, heat treatment (including irradiation with a laserbeam), or the like is desirably performed on the semiconductor film 140(see FIG. 6E). The descriptions of FIGS. 6D and 6E follow thedescriptions of FIGS. 3D and 3E, respectively. Note that, here, since asingle-crystal silicon substrate is used as the semiconductor substrate102, a single-crystal silicon thin film can be obtained as thesemiconductor film 140.

By heat treatment shown in FIG. 6D, halogen contained in the secondthermal oxide film 153 is distributed again and diffused to thesemiconductor film 140 (the semiconductor substrate 102) side. As aresult, dangling bonds at the separation surface of the semiconductorfilm 140, in the semiconductor film 140, and at an interface between thesemiconductor film 140 and the thermal oxide film are terminated. Here,when a single-crystal silicon film is formed as the semiconductor film140 and the second thermal oxide film 153 contains fluorine, Si—F bondsare generated in regions where dangling bonds are terminated.

Note that, since halogen is diffused from the second thermal oxide film153 to the semiconductor film 140 by the heat treatment for separatingthe semiconductor substrate 102, the amount of halogen contained in thesecond thermal oxide film 153 is decreased. Thus, after the heattreatment, a thermal oxide film 155 (hereinafter, referred to as a thirdthermal oxide film 155) is obtained which is the second thermal oxidefilm 153 in which the amount of halogen is decreased. Note that halogenis contained in the third thermal oxide film 155, whereby a getteringeffect of metal impurities or the like can be expected.

The semiconductor film 140 is terminated by halogen, and halogen iscontained in the semiconductor film 140. Halogen is desirably containedin the semiconductor film 140 at a peak concentration of the range of1×10¹⁷ atoms/cm³ to 1×10²¹ atoms/cm³.

Through the above-described steps, a semiconductor device manufacturingsubstrate can be manufactured in which the semiconductor film 140 isbonded to the supporting substrate 120 with the bonding layer 114, theinsulating film 106 containing silicon and nitrogen as its composition,and the third thermal oxide film 155 which are stacked in order over thesupporting substrate 120 interposed therebetween.

Note that it is acceptable as long as the method for manufacturing thesemiconductor device manufacturing substrate in this embodiment modeenables dangling bonds in the semiconductor film obtained by separationof the semiconductor film by embrittlement by irradiation with ionsgenerated with use of hydrogen as a source gas and heat treatment can beterminated with use of halogen contained in advance in the insulatingfilm formed between the supporting substrate and the semiconductor film,and there is no particular limitation on the order of steps. In thisembodiment mode, the example is described in which the insulating film104 containing silicon and oxygen as its composition (or the thermaloxide film 103) and the insulating film 106 containing silicon andnitrogen as its composition are stacked over the semiconductor substrate102, the semiconductor substrate 102 is irradiated with hydrogen ordeuterium to which ionization has been performed to form the separationlayer 112, and then the insulating film 104 containing silicon andoxygen as its composition (or the thermal oxide film 103) is irradiatedwith halogen ions to form the bonding layer 114 over the insulating film106 containing silicon and nitrogen as its composition. However, theorder of the steps up to formation of the bonding layer 114 over thesemiconductor substrate 102 can be changed as appropriate.

For example, the step of forming the separation layer 112 may beperformed before the step of forming the insulating film 104 containingsilicon and oxygen as its composition and the insulating film 106containing silicon and nitrogen as its composition over thesemiconductor substrate 102 or after the step of forming the insulatingfilm 104 containing silicon and oxygen as its composition and before thestep of forming the insulating film 106 containing silicon and nitrogenas its composition. Note that, when the semiconductor substrate 102 isprovided with the thermal oxide film 103, the separation layer 112 isdesirably formed after the thermal oxide film 103 is formed. This isbecause the semiconductor substrate 102 can be separated at theseparation layer 112 at the time of thermal oxidation. Alternatively,the step of forming the separation layer 112 may be performed after thestep of irradiation of the insulating film 104 containing silicon andoxygen as its composition with the halogen ions 113 or after the step offorming the bonding layer 114 over the insulating film 106 containingsilicon and nitrogen as its composition. In addition, the step ofirradiation with the halogen ions 113 may be performed at least afterthe step of forming the insulating film 104 containing silicon andoxygen as its composition over the semiconductor substrate 102, and maybe performed before the step of forming the insulating film 106containing silicon and nitrogen as its composition or after the step offorming the bonding layer 114.

For example, after the insulating film 104 containing silicon and oxygenas its composition, the insulating film 106 containing silicon andnitrogen as its composition, and the bonding layer 114 are formed overthe semiconductor substrate 102 and the semiconductor substrate 102 isirradiated with the ions 108 which are obtained by ionization ofhydrogen or deuterium to form the separation layer 112, the insulatingfilm 104 containing silicon and oxygen as its composition is irradiatedwith the halogen ions 113 to obtain the insulating film 105 containingsilicon and oxygen as its composition in which the halogen arecontained. Alternatively, in this case, after formation of the bondinglayer 114 and irradiation of the insulating film 104 containing siliconand oxygen as its composition with the halogen ions 113 to obtain theinsulating film 105 containing silicon and oxygen as its composition inwhich the halogen are contained, the separation layer 112 can be formedby irradiation of the semiconductor substrate 102 with the ions 108which are obtained by ionization of hydrogen or deuterium.

In this embodiment mode, dangling bonds in the semiconductor filmincluded in the semiconductor device manufacturing substrate areterminated by halogen. Thus, improvement of semiconductorcharacteristics is achieved, and manufacture of a semiconductor devicewhich has good electric characteristics can be realized with use of thesemiconductor device manufacturing substrate of this embodiment mode.Note that this embodiment mode can be combined as appropriate with otherembodiment modes described in this specification.

Embodiment Mode 2

In this embodiment mode, an example of manufacturing a semiconductordevice with use of a semiconductor device manufacturing substrate of thepresent invention will be described with reference to FIGS. 11A to 11Dand FIGS. 12A and 12B.

A semiconductor device manufacturing substrate is prepared (see FIG.11A). In this embodiment mode, an example of using the semiconductordevice manufacturing substrate which has an SOI structure shown in FIG.1, in which the semiconductor film 140 is bonded to the supportingsubstrate 120 with the bonding layer 114, the insulating film 106containing silicon and nitrogen as its composition, and the thirdinsulating film 107 containing silicon and oxygen as its compositionwhich are stacked in order over the supporting substrate 120 interposedtherebetween, is described. Note that there is no particular limitationon the structure of the semiconductor device manufacturing substrate ofthe present invention, and a semiconductor device manufacturingsubstrate which has another structure described in this specificationcan be applied.

A substrate with an insulating surface or a substrate with an insulatingproperty is used as the supporting substrate 120. For example, variousglass substrates (also referred to as a non-alkali glass substrate) usedin the electronics industry, such as an aluminosilicate glass substrate,an aluminoborosilicate glass substrate, or a barium borosilicate glasssubstrate; a quartz substrate; a ceramic substrate; a sapphiresubstrate; a metal substrate whose surface is coated with an insulatingfilm; or the like is used.

A film which has a smooth surface and can form a hydrophilic surface isdesirably formed as the bonding layer 114. For example, a silicon oxidefilm or a film which has siloxane bonds is formed as the bonding layer114. The insulating film 106 containing silicon and nitrogen as itscomposition functions as a blocking film. The insulating film 106containing silicon and nitrogen as its composition may be formed of, forexample, a silicon nitride film or a silicon nitride oxide film. Theformation of the insulating film 106 containing silicon and nitrogen asits composition makes it possible to block diffusion of metal impuritiesfrom the supporting substrate 120 to the semiconductor film 140 side. Inaddition, the bonding layer 114 is located between the insulating film106 containing silicon and nitrogen as its composition and thesupporting substrate 120, whereby functions are obtained in whichbonding layer 114 reduces the internal stress of the insulating film 106containing silicon and nitrogen as its composition and reducesdistortion due to stress by different kinds of materials.

Halogen is contained in the third insulating film 107 containing siliconand oxygen as its composition. As the third insulating film 107containing silicon and oxygen as its composition, a silicon oxide filmor a silicon oxynitride film may be formed. Needless to say, a thermaloxide film may be used as the third insulating film 107 containingsilicon and oxygen as its composition. The third insulating film 107containing silicon and oxygen as its composition contains halogen,whereby it has a gettering effect of metal impurities or the like. Inaddition, the third insulating film 107 containing silicon and oxygen asits composition is located between the semiconductor film 140 and theinsulating film 106 containing silicon and nitrogen as its composition,whereby trap levels can be prevented from being formed at an interfaceof the semiconductor film 140, and improvement of electriccharacteristics can be achieved.

Note that the thickness of each of the bonding layer 114, the insulatingfilm 106 containing silicon and nitrogen as its composition, and thethird insulating film 107 containing silicon and oxygen as itscomposition may be determined as appropriate by a practitioner. Forexample, the bonding layer 114 can be formed to a thickness of greaterthan or equal to 5 nm and less than or equal to 500 nm, preferablygreater than or equal to 10 nm and less than or equal to 100 nm; theinsulating film 106 containing silicon and nitrogen as its compositioncan be formed to a thickness of greater than or equal to 10 nm and lessthan or equal to 200 nm, preferably greater than or equal to 50 nm andless than or equal to 100 nm; and the third insulating film 107containing silicon and oxygen as its composition can be formed to athickness of greater than or equal to 10 nm and less than or equal to500 nm, preferably greater than or equal to 50 nm and less than or equalto 200 nm.

The semiconductor film 140 is formed to a thickness of greater than orequal to 5 nm and less than or equal to 500 nm, preferably greater thanor equal to 10 nm and less than or equal to 200 nm, further preferablygreater than or equal to 10 nm and less than or equal to 60 nm. Thethickness of the semiconductor film 140 can be set by control of thedepth where the separation layer 112 is formed, which is described inthe above embodiment mode. In addition, the semiconductor film 140 ofthe semiconductor device manufacturing substrate may be thinned byetching or the like to a desired thickness. The semiconductor film 140can be thinned by dry etching with use of a chlorine-based gas such asCl₂, BCl₃, or SiCl₄; a fluorine-based gas such as CF₄, NF₃, or SF₆; oran HBr gas; or the like. Alternatively, the semiconductor film 140 canbe partially altered by oxidation treatment, nitridation treatment, orthe like, and the altered portion can be selectively etched.

Halogen is contained in the semiconductor film 140. Halogen is desirablycontained in the semiconductor film 140 at a peak concentration of therange of 1×10¹⁷ atoms/cm³ to 1×10²¹ atoms/cm³. In addition, althoughhalogen contained in the semiconductor film 140 can be uniformlydistributed, halogen may be distributed in the semiconductor film 140 soas to have a local peak concentration. When halogen is distributed inthe semiconductor film 140 while having a local peak concentration, thepeak concentration desirably exists in the vicinity of an interface oron the side close to a separation surface where a dangling bond iseasily formed.

In addition, it is desirable to add a p-type impurity element such asboron, aluminum, or gallium, or an n-type impurity element such asphosphorus or arsenic to the semiconductor film 140 in accordance withregions where an n-channel field effect transistor and a p-channel fieldeffect transistor are formed. That is, so-called well regions are formedby addition of a p-type impurity element in accordance with a formationregion of an n-channel field effect transistor and addition of an n-typeimpurity element in accordance with a formation region of a p-channelfield effect transistor. The dose of impurity ions may be approximatelygreater than or equal to 1×10¹² ions/cm² and less than or equal to1×10¹⁴ ions/cm². Furthermore, when threshold voltage of the field effecttransistor is controlled, a p-type impurity element or an n-typeimpurity element may be added to these well regions.

Next, the semiconductor film 140 is selectively etched to form asemiconductor film 140 a and a semiconductor film 140 b which areseparated into island shapes in accordance with arrangement ofsemiconductor elements (see FIG. 11B).

Note that, although the example in which element isolation is performedby etching of the semiconductor film 140 into the island shape isdescribed in this embodiment mode, the present invention is notparticularly limited thereto. For example, element isolation may beperformed by embedding of an insulating film between semiconductor filmsin accordance with arrangement of semiconductor elements.

Next, a gate insulating film 711, a gate electrode 712, and sidewallinsulating films 713 are formed over each of the semiconductor film 140a and the semiconductor film 140 b. The sidewall insulating films 713are provided on side surfaces of the gate electrode 712. Then, a firstimpurity region 714 a and a second impurity region 715 a are formed inthe semiconductor film 140 a, and a first impurity region 714 b and asecond impurity region 715 b are formed in the semiconductor film 140 b.Note that an insulating film 716 is formed over the gate electrode 712.The insulating film 716 is formed of a silicon nitride film and used asa hard mask for etching when forming the gate electrode 712 (see FIG.11C).

Note that conductive films for forming the gate insulating film 711, thesidewall insulating films 713, the insulating film 716, and the gateelectrode 712 are preferably formed at a temperature less than thetemperature of the heat treatment for separating a semiconductorsubstrate in the semiconductor device manufacturing substrate. This isbecause halogen which terminates the semiconductor film 140 is preventedfrom being desorbed.

Next, a protective film 717 is formed so as to cover the gate electrodes712 and the like provided for the semiconductor device manufacturingsubstrate (see FIG. 11D). The protective film 717 prevents contaminationdue to metal impurities from the upper layer side, whereas theinsulating film 106 containing silicon and nitrogen as its compositionprevents diffusion of metal impurities from the supporting substrate 120side. In this embodiment mode, the lower layer side and the upper layerside of the semiconductor film 140 which has excellent crystallinity arecoated with an insulating film having a high blocking effect of metalimpurities with high mobility, such as sodium. Thus, a profound effecton improvement of electric characteristics of the semiconductor elementsmanufactured using the semiconductor film 140 can be achieved.

An interlayer insulating film 718 is formed over the protective film717. The interlayer insulating film 718 may be formed of a BPSG (boronphosphorus silicon glass) film or may be formed by application of anorganic resin typified by polyimide. Then, contact holes 719 are formedin the interlayer insulating film 718. Note that the protective film 717and the interlayer insulating film 718 are formed at a temperature lessthan the temperature of the heat treatment for separating thesemiconductor substrate in the semiconductor device manufacturingsubstrate in order to prevent desorption of halogen in the semiconductorfilm 140.

Next, a step of forming wirings is described. Contact plugs 723 areformed in the contact holes 719. The contact plugs 723 are formed insuch a manner that tungsten silicide is formed by a CVD method with useof a WF₆ gas and a SiH₄ gas and embedded in the contact holes 719.Alternatively, tungsten may be formed by hydrogen reduction of WF₆ andembedded in the contact holes 719. After that, wirings 721 are formed inaccordance with the contact plugs 723. The wirings 721 are formed ofaluminum or an aluminum alloy, and upper layers and lower layers of thewirings 721 are formed of a metal film of molybdenum, chromium, ortitanium as barrier metal. Furthermore, another interlayer insulatingfilm 718 is formed over the upper layers of the wirings 721 (see FIG.12B). The wirings may be provided as appropriate, and multilayer wiringsmay be formed by further formation of wiring layers over the upperlayers. In that case, a damascene process may be employed.

Note that the processing temperature of the formation of the wirings orthe like is set to less than the temperature of the heat treatment forseparating the semiconductor substrate in the semiconductor devicemanufacturing substrate in order to prevent desorption of halogen in thesemiconductor film 140. As described above, the temperature of the heattreatment for separating the semiconductor substrate is set as thehighest temperature of the process and the processing temperatures ofother steps are set to less than the temperature of the heat treatment,whereby desorption of halogen which terminates dangling bonds in thesemiconductor film 140 can be prevented.

Through the above-described steps, a field effect transistor can bemanufactured with use of the semiconductor device manufacturingsubstrate which has the semiconductor film bonded to the supportingsubstrate with a stacked structure of the insulating films interposedtherebetween. Improvement in electric characteristics of thesemiconductor device manufacturing substrate of the present invention isachieved, and thus a field effect transistor which has good operatingcharacteristics can be provided. In addition, an insulating filmcontaining silicon and oxygen as its composition in which halogen iscontained and an insulating film containing silicon and nitrogen as itscomposition each of which has a high gettering effect of metalimpurities or a high blocking effect thereof is formed, and thus asemiconductor device with high reliability can be manufactured.Furthermore, application of the present invention makes it possible toform the semiconductor film 140 using a single-crystal semiconductor,and thus higher performance of the semiconductor device can be achieved.

Note that this embodiment mode can be combined as appropriate with otherembodiment modes described in this specification.

Embodiment Mode 3

In this embodiment mode, an example of manufacturing a semiconductordevice with use of a semiconductor device manufacturing substrate of thepresent invention will be described with reference to FIGS. 7A to 7E,FIGS. 8A to 8C, FIGS. 9A and 9B, and FIGS. 10A and 10B. In thisembodiment mode, an example of manufacturing an electroluminescence (EL)display device will be described.

A semiconductor device manufacturing substrate is prepared (see FIG.7A). In this embodiment mode, an example of using a semiconductor devicemanufacturing substrate which has an SOI structure in which thesemiconductor film 140 is bonded to the supporting substrate 120 withthe barrier film 122, the bonding layer 124, the bonding layer 114, theinsulating film 106 containing silicon and nitrogen as its composition,and the third thermal oxide film 155 which are stacked in order over thesupporting substrate 120 interposed therebetween is described. Thesemiconductor device manufacturing substrate described in thisembodiment mode is an example in which the bonding layer is alsoprovided over the supporting substrate in the structure shown in FIGS.6A to 6E. That is, the structure of the supporting substrate shown inFIG. 4B is employed. Note that the present invention is not particularlylimited thereto, and a semiconductor device manufacturing substratewhich has another structure described in this specification can also beemployed.

A substrate with an insulating surface or a substrate with an insulatingproperty is used as the supporting substrate 120. For example, variousglass substrates (also referred to as a non-alkali glass substrate) usedin the electronics industry, such as an aluminosilicate glass substrate,an aluminoborosilicate glass substrate, or a barium borosilicate glasssubstrate; a quartz substrate; a ceramic substrate; a sapphiresubstrate; a metal substrate whose surface is coated with an insulatingfilm; or the like is used.

A film which has a smooth surface and can form a hydrophilic surface isformed as the bonding layer 114 and the bonding layer 124. For example,a silicon oxide film or a film which has siloxane bonds is formed. Notethat the bonding layer 124 is needed to form in consideration of theheat resistance of the supporting substrate 120. When a glass substrateis used as the supporting substrate 120, the bonding layer 124 is formedat a temperature of less than or equal to 650° C. For example, thebonding layer 124 can be formed by a CVD method with use of organicsilane such as TEOS as a source gas. As the barrier film 122 providedbetween the supporting substrate 120 and the bonding layer 124, a filmwhich has an effect of blocking metal impurities, such as a siliconnitride film, a silicon nitride oxide film, or an aluminum nitride filmis formed. Note that, in the case where the bonding layer 124 and thebarrier film 122 are formed over the supporting substrate 120, thebarrier film 122 is formed as a bottom layer (on the supportingsubstrate 120 side) and the bonding layer 124 is formed as an upperlayer (the semiconductor film 140 side), whereby internal stress of thebarrier film 122 can be reduced. The insulating film 106 containingsilicon and nitrogen as its composition may be formed of a siliconnitride film or a silicon nitride oxide film.

The third thermal oxide film 155 is formed by thermal oxidation of thesemiconductor substrate. In addition, halogen is contained in the thirdthermal oxide film 155.

Note that the thickness of each of the barrier film 122, the bondinglayer 124, the bonding layer 114, the insulating film 106 containingsilicon and nitrogen as its composition, and the third thermal oxidefilm 155 may be determined as appropriate by a practitioner. Thethickness of the third thermal oxide film 155 can be controlled byprocessing time or the like of the thermal oxidation.

The semiconductor film 140 is formed to a thickness of greater than orequal to 5 nm and less than or equal to 500 nm, preferably greater thanor equal to 10 nm and less than or equal to 200 nm, further preferablygreater than or equal to 10 nm and less than or equal to 60 nm. Thethickness of the semiconductor film 140 can be set by control of thedepth where the separation layer 112 is formed, which is described inthe above embodiment mode. In addition, the semiconductor film 140 ofthe semiconductor device manufacturing substrate may be thinned byetching or the like to a desired thickness. The semiconductor film 140can be thinned by dry etching with use of a chlorine-based gas such asCl₂, BCl₃, or SiCl₄; a fluorine-based gas such as CF₄, NF₃, or SF₆; oran HBr gas; or the like. Alternatively, the semiconductor film 140 canbe partially altered by oxidation treatment, nitridation treatment, orthe like and the altered portion can be selectively etched.

Halogen is contained in the semiconductor film 140. Halogen is desirablycontained in the semiconductor film 140 at a peak concentration of therange of 1×10¹⁷ atoms/cm³ to 1×10²¹ atoms/cm³. In addition, althoughhalogen contained in the semiconductor film 140 can be uniformlydistributed, halogen may be distributed in the semiconductor film 140 soas to locally have a peak concentration. When halogen is distributed inthe semiconductor film 140 while having a local peak concentration, thepeak concentration desirably exists in the vicinity of an interface oron the side close to a separation surface where a dangling bond iseasily formed. It is desirable to add a p-type impurity element such asboron, aluminum, or gallium, or an n-type impurity element such asphosphorus or arsenic to the semiconductor film 140 in accordance withregions where field effect transistor are formed. That is, so-calledwell regions are formed by addition of a p-type impurity element inaccordance with a formation region of an n-channel field effecttransistor and addition of an n-type impurity element in accordance witha formation region of a p-channel field effect transistor. The dose ofimpurity ions may be approximately greater than or equal to 1×10¹²ions/cm² and less than or equal to 1×10¹⁴ ions/cm². Furthermore, whenthreshold voltage of a field effect transistor is controlled, a p-typeimpurity element or an n-type impurity element may be added to thesewell regions.

Next, the semiconductor film 140 is selectively etched to form asemiconductor film 140 c and a semiconductor film 140 d which areseparated into island shapes in accordance with arrangement ofsemiconductor elements (see FIG. 7B).

Next, a gate insulating film 810, and a first conductive film 812 and asecond conductive film 814 which form a gate electrode are formed inorder over the semiconductor film 140 c and the semiconductor film 140 d(see FIG. 7C).

The gate insulating film 810 is formed as a single-layer film or astacked-layer film using an insulating film such as a silicon oxidefilm, a silicon oxynitride film, a silicon nitride film, or a siliconnitride oxide film by a CVD method, a sputtering method, an atomic layerepitaxy method, or the like.

Alternatively, the gate insulating film 810 may be followed in such amanner that plasma treatment is performed on the semiconductor film 140c and the semiconductor film 140 d to oxidize or nitride surfacesthereof. The plasma treatment in this case includes plasma treatmentusing plasma excited by a microwave (a typical frequency of 2.45 GHz),for example, treatment using plasma which is excited by a microwave andhas an electron density of greater than or equal to 1×10¹¹ cm³ and lessthan or equal to 1×10¹³ cm³ and an electron temperature of greater thanor equal to 0.5 eV and less than or equal to 1.5 eV. Oxidation treatmentor nitridation treatment of the surface of the semiconductor film withsuch plasma treatment makes it possible to form a thin and dense film.In addition, the surface of the semiconductor film is directly oxidized,and thus a film which has good interface characteristics can beobtained. Note that the gate insulating film 810 may be formed in such amanner that plasma treatment using a microwave is performed on a filmformed by a CVD method, a sputtering method, or an atomic layer epitaxymethod.

Note that, since the gate insulating film 810 forms an interface withthe semiconductor film, the gate insulating film 810 on the side whichis in contact with the semiconductor film is desirably formed of asilicon oxide film or a silicon oxynitride film. This is because, if afilm in which the amount of nitrogen is higher than that of oxygen, suchas a silicon nitride film or a silicon nitride oxide film is formed,problems of surface characteristics such as generation of a fixed chargedue to formation of trap levels might be generated.

The conductive film which forms the gate electrode is formed as asingle-layer film or a stacked-layer film using an element selected fromtantalum, tantalum nitride, tungsten, titanium, molybdenum, aluminum,copper, chromium, or niobium, an alloy material or a compound materialcontaining the element as its main component, or a semiconductormaterial typified by polycrystalline silicon doped with an impurityelement such as phosphorus, by a CVD method or a sputtering method. Whenthe conductive film is formed as a stacked film, it can be formed usingdifferent conductive materials or can be formed using the sameconductive material. In this embodiment mode, the example is describedin which the first conductive film 812 and the second conductive film814 are used as the conductive film which forms the gate electrode.

When the conductive film which forms the gate electrode has a two-layerstructure of the first conductive film 812 and the second conductivefilm 814, for example, a stacked film of a tantalum nitride film and atungsten film, a stacked film of a tungsten nitride film and a tungstenfilm, or a stacked film of a molybdenum nitride film and a molybdenumfilm can be formed. Note that a stacked film of a tantalum nitride filmand a tungsten film is preferable because etching rates of both filmsare easily differentiated from each other and high selectivity can beobtained. Note that, in for the two-layer films which are exemplified,the first mentioned film is preferably formed over the gate insulatingfilm 810. Here, the first conductive film 812 is formed to a thicknessof greater than or equal to 20 nm and less than or equal to 100 nm. Thesecond conductive film 814 is formed to a thickness of greater than orequal to 100 nm and less than or equal to 400 nm. Note that the gateelectrode can have a stacked structure of three or more layers. In thatcase, a stacked structure of a molybdenum film, an aluminum film, amolybdenum film may be employed.

Note that the gate insulating film 810, and the first conductive film812 and the second conductive film 814 which form the gate electrode aredesirably formed at a temperature less than or equal to the temperatureof the heat treatment for separating the semiconductor substrate, inorder to prevent desorption of halogen which terminates thesemiconductor film 140.

Next, a resist mask 820 c and a resist mask 820 d are selectively formedover the second conductive film 814. Then, first etching treatment andsecond etching treatment are performed using the resist mask 820 c andthe resist mask 820 d.

First, the first conductive film 812 and the second conductive film 814are selectively etched by the first etching treatment to form a firstconductive film 816 c and a second conductive film 818 c over thesemiconductor film 140 c, and to form a first conductive film 816 d anda second conductive film 818 d over the semiconductor film 140 d (seeFIG. 7D).

Next, edge portions of the second conductive film 818 c and the secondconductive film 818 d are selectively etched by the second etchingtreatment to form a second conductive film 822 c and a second conductivefilm 822 d (see FIG. 7E). Note that the second conductive film 822 c andthe second conductive film 822 d are formed so that the widths (thelengths in a direction parallel to a direction in which carriers flow ina channel formation region (a direction connecting a source region and adrain region)) of the second conductive film 822 c and the secondconductive film 822 d are smaller than the widths of the firstconductive film 816 c and the first conductive film 816 d, respectively.In this manner, a gate electrode 824 c formed of the first conductivefilm 816 c and the second conductive film 822 c, and a gate electrode824 d formed of the first conductive film 816 d and the secondconductive film 822 d can be obtained.

Although an etching method employed for the first etching treatment andthe second etching treatment may be selected as appropriate, a dryetching apparatus using a high-density plasma source such as ECR(electron cyclotron resonance) or ICP (inductive coupled plasma) may beused in order to increase the etching rate. Etching conditions of thefirst etching treatment and the second etching treatment are controlledas appropriate, whereby side surfaces of the first conductive films 816c and 816 d and the second conductive films 822 c and 822 d can beformed into predetermined tapered shapes. The resist masks 820 c and 820d may be removed after the desired gate electrodes 824 c and 824 d areformed.

Next, an impurity element 880 is added to the semiconductor film 140 cand the semiconductor film 140 d with use of the gate electrode 824 cand the gate electrode 824 d as masks, respectively. In thesemiconductor film 140 c, a pair of first impurity regions 826 c isformed in a self-alignment manner with use of the first conductive film816 c and the second conductive film 822 c as masks. In addition, in thesemiconductor film 140 d, a pair of first impurity regions 826 d isformed in a self-alignment manner with use of the first conductive film816 d and the second conductive film 822 d as masks (see FIG. 8A).

As the impurity element 880, a p-type impurity element such as boron,aluminum, or gallium, or an n-type impurity element such as phosphorusor arsenic is added. Here, phosphorus that is an n-type impurity elementis added so as to be contained at a concentration of about greater thanor equal to 1×10¹⁷ atoms/cm³ and less than or equal to 5×10¹⁸ atoms/cm³.

Next, a resist mask 882 is selectively formed so as to cover thesemiconductor film 140 d. In addition, a resist mask 881 is formed so asto partially cover the semiconductor film 140 c. Then, an impurityelement 884 is added with use of the resist mask 882 and the resist mask881 as masks to form a pair of second impurity regions 828 c, a pair ofthird impurity regions 830 c, and a channel formation region 142 c inthe semiconductor film 140 c (see FIG. 8B).

As the impurity element 884, a p-type impurity element such as boron,aluminum, or gallium, or an n-type impurity element such as phosphorusor arsenic is added. Here, phosphorus that is an n-type impurity elementis added so as to be contained at a concentration of about greater thanor equal to 5×10¹⁹ atoms/cm³ and less than or equal to 5×10²⁰ atoms/cm³.

In the semiconductor film 140 c, the second impurity regions 828 c areformed in regions which do not overlap with the first conductive film816 c and the second conductive film 822 c. The channel formation region142 c is formed in a region which overlaps with the first conductivefilm 816 c and the second conducive film 822 c. The third impurityregions 830 c are each formed between the channel formation region 142 cand the second impurity region 828 c and formed in a region which doesnot overlap with the first conductive film 816 c and the secondconducive film 822 c. In addition, the third impurity regions 830 c areformed in regions which do not overlap with the first conductive film816 c and the second conducive film 822 c and in regions which overlapwith the resist mask 881. The second impurity regions 828 c function asa source region and a drain region. In addition, the third impurityregions 830 c function as LDD regions. In this embodiment mode, theimpurity concentration of the second impurity region 828 c is higherthan that of the third impurity region 830 c.

Note that an LDD region refers to a region to which an impurity elementis added at low concentration between a channel formation region and asource region or a drain region which is formed by being added with animpurity element at high concentration. When an LDD region is provided,there is an advantageous effect in that an electric field in thevicinity of a drain region is reduced to prevent deterioration due tohot carrier injection. In order to prevent deterioration of on currentdue to hot carriers, a structure (also referred to as a GOLD (gate-drainoverlapped LDD) structure) may be employed in which an LDD regionoverlaps with a gate electrode with a gate insulating film interposedtherebetween.

Next, the resist mask 881 and the resist mask 882 are removed, and thena resist mask 886 is formed so as to cover the semiconductor film 140 c.Then, an impurity element 888 is added with use of the resist mask 886,the first conductive film 816 d, and the second conductive film 822 d asmasks to form a pair of second impurity regions 828 d, a pair of thirdimpurity region 830 d, and a channel formation region 142 d in thesemiconductor film 140 d (see FIG. 8C).

As the impurity element 888, a p-type impurity element such as boron,aluminum, or gallium, or an n-type impurity element such as phosphorusor arsenic is added. Here, boron that is a p-type impurity region isadded so as to be contained at a concentration of about greater than orequal to 1×10²⁰ atoms/cm³ and less than or equal to 5×10²¹ atoms/cm³. Inthe semiconductor film 140 d, the second impurity regions 828 d areformed in regions which do not overlap with the first conductive film816 d and the second conductive film 822 d. The third impurity regions830 d are formed in regions which overlap with the first conductive film816 d and do not overlap with the second conductive film 822 d. Theimpurity element 888 penetrates the first conductive film 816 d to formthe third impurity regions 830 d. The second impurity regions 828 dfunction as a source region and a drain region. In addition, the thirdimpurity regions 830 d function as LDD regions. In this embodiment mode,the impurity concentration of the second impurity region 828 d is higherthan that of the third impurity region 830 d.

Next, an interlayer insulating film is formed. Although the interlayerinsulating film can be formed as either a single-layer film or astacked-layer film, it is formed so as to have a stacked structure of aninsulating film 832 and an insulating film 834 in this embodiment mode(see FIG. 9A).

As the interlayer insulating film, a silicon oxide film, a siliconoxynitride film, a silicon nitride film, a silicon nitride oxide film,or the like can be formed by a CVD method or a sputtering method.Alternatively, the interlayer insulating film can be formed using anorganic material such as polyimide, polyamide, polyvinyl phenol,benzocyclobutene, acrylic, or epoxy; a siloxane material such as asiloxane resin; an oxazole resin; or the like by an application methodsuch as a spin coating method. Note that a siloxane material correspondsto a material which has a Si—O—Si bond. Siloxane includes a skeletonstructure of a bond of silicon (Si) and oxygen (O). As a substituent, anorganic group containing at least hydrogen (e.g., an alkyl group oraromatic hydrocarbon) is used. Alternatively, a fluoro group can be usedas a substituent. Further alternatively, a fluoro group and an organicgroup containing at least hydrogen can be used as a substituent. Anoxazole resin is, for example, photosensitive polybenzoxazole or thelike. Photosensitive polybenzoxazole is a material which has a lowdielectric constant (a dielectric constant of 2.9 at 1 MHz at roomtemperature), high heat resistance (according to results ofthermogravimetry-differential thermal analysis (TG-DTA), it has athermal decomposition temperature of 550° C. at a rate of temperatureincrease of 5° C./min), and a low water absorption coefficient (0.3% atroom temperature for 24 hours). Since an oxazole resin has a lowerdielectric constant (about 2.9) than a dielectric constant of polyimideor the like (approximately 3.2 to 3.4). Thus, when an oxazole resin isused, generation of parasitic capacitance can be suppressed andhigh-speed operation is possible.

For example, a silicon nitride oxide film is formed to a thickness of100 nm as the insulating film 832, and a silicon oxynitride film isformed to a thickness of 900 nm as the insulating film 834. In addition,the insulating film 832 and the insulating film 834 are successivelyformed by a plasma CVD method. Note that the interlayer insulating filmcan also have a stacked structure of three or more layers.Alternatively, a stacked structure of a silicon oxide film, a siliconoxynitride film, or a silicon nitride film and an insulating film formedusing an organic material such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, or epoxy; a siloxane material such asa siloxane resin; or an oxazole resin can be employed.

Note that, in order to prevent desorption of halogen which terminatesdangling bonds in the semiconductor film 140, the interlayer insulatingfilm (in this embodiment mode, the insulating film 832 and theinsulating film 834) is desirably formed at a temperature less than thetemperature of the heat treatment for separating the semiconductorsubstrate.

Next, contact holes are formed in the interlayer insulating film (inthis embodiment mode, the insulating film 832 and the insulating film834), and conductive films 836 which function as a source electrode anda drain electrode are formed in the contact holes (see FIG. 9B).

The contact holes are selectively formed in the insulating film 832 andthe insulating film 834 so as to reach the second impurity regions 828 cformed in the semiconductor film 140 c and the second impurity regions828 d formed in the semiconductor film 140 d.

As the conductive film 836, a single-layer film or a stacked-layer filmformed of one element selected from aluminum, tungsten, titanium,tantalum, molybdenum, nickel, or neodymium or formed of an alloycontaining a plurality of the above-described elements can be used. Forexample, as a conductive film formed of an alloy containing a pluralityof the above-described elements, an aluminum alloy containing titanium,an aluminum alloy containing neodymium, or the like can be used.Furthermore, in the case of a stacked film, for example, a structure canbe employed in which an aluminum film or an aluminum alloy film asdescribed above is interposed between titanium films.

Next, a step of forming a light-emitting element 850 is described (seeFIG. 10A). Here, an example of forming an organic light-emitting elementprovided with an organic compound-containing layer as a light-emittinglayer is described.

First, a pixel electrode 840 is formed so as to be electricallyconnected to the conductive film 836. The pixel electrode 840 iselectrically connected to the second impurity region 828 d formed in thesemiconductor film 140 d with the conductive film 836 interposedtherebetween. After a partition film 842 which covers an edge portion ofthe pixel electrode 840 is formed, an organic compound-containing layer844 and a counter electrode 846 are stacked over the pixel electrode840.

Note that, although the example in which the pixel electrode 840 isformed over an insulating film 838 provided over the conductive films836 is described here, the present invention is not particularly limitedthereto. For example, a structure may also be employed in which thepixel electrode 840 is provided over the insulating film 834. In thatcase, the pixel electrode 840 can also be formed using part of theconductive film 836 which functions as a source electrode or a drainelectrode.

As the insulating film 838, a silicon oxide film, a silicon oxynitridefilm, a silicon nitride film, or the like can be formed by a CVD methodor a sputtering method. Alternatively, the insulating film 838 can beformed using an organic material such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, or epoxy; a siloxane material such asa siloxane resin; an oxazole resin; or the like by an application methodsuch as a spin coating method. Note that the insulating film 838 can beformed as a single-layer film or a stacked-layer film using theabove-described material.

Either one of the pixel electrode 840 and the counter electrode 846functions as an anode, and the other functions as a cathode. As forlight emission of the light-emitting element, there are the case wherelight is extracted from the supporting substrate 120 side (also referredto as bottom emission), the case where light is extracted from the sideopposite to the supporting substrate 120 side (also referred to as topemission), and the case where light is extracted from the supportingsubstrate 120 side and the side opposite thereto (also referred to asdual emission). In the case of bottom emission, it is desirable that thepixel electrode 840 be formed as a light-transmitting electrode and thecounter electrode 846 as a reflective electrode. In the case of topemission, on the other hand, it is desirable that the pixel electrode840 be formed as a reflective electrode and the counter electrode as alight-transmitting electrode. In the case of dual emission, it isdesirable that both the pixel electrode 840 and the counter electrode846 be formed as light-transmitting electrodes.

When the pixel electrode 840 or the counter electrode 846 is formed as areflective electrode, it can be formed using a reflective conductivematerial, for example, a metal element such as tantalum, tungsten,titanium, molybdenum, aluminum, chromium, or silver, or an alloymaterial or a compound material containing the above-described metalelement.

When the pixel electrode 840 or the counter electrode 846 is formed as alight-transmitting electrode, it can be formed using alight-transmitting conductive material such as indium tin oxide (ITO),zinc oxide (ZnO), indium zinc oxide (IZO), or zinc oxide doped withgallium (GZO). In addition, an electrode through which visible light istransmitted can be obtained by formation of a film of a reflectiveconductive material to a thickness of several to several tens ofnanometers.

A light-transmitting electrode can be formed using a conductivecomposition containing a conductive high molecule (also referred to as aconductive polymer). A thin film of an electrode formed using aconductive composition desirably has a sheet resistance of less than orequal to 10000 Ω/square and a light transmittance of greater than orequal to 70% at a wavelength of 550 nm. In addition, the resistance ofthe conductive high molecule which is contained in the conductivecomposition is desirably less than or equal to 0.1 Ω·cm.

As a conductive high molecule, a so-called π electron conjugated highmolecule can be used. For example, polyaniline or a derivative thereof,polypyrrole or a derivative thereof, polythiophene or a derivativethereof, and a copolymer of two or more kinds of those materials can begiven.

As specific examples of a conjugated conductive high molecule, thefollowing are given: polypyrrole, poly(3-methylpyrrole),poly(3-butylpyrrole), poly(3-octylpyrrole), poly(3-decylpyrrole),poly(3,4-dimethylpyrrole), poly(3,4-dibutylpyrrole),poly(3-hydroxypyrrole), poly(3-methyl-4-hydroxypyrrole),poly(3-methoxypyrrole), poly(3-ethoxypyrrole), poly(3-octoxypyrrole),poly(3-carboxylpyrrole), poly(3-methyl-4-carboxylpyrrole),polyN-methylpyrrole, polythiophene, poly(3-methylthiophene),poly(3-butylthiophene), poly(3-octylthiophene), poly(3-decylthiophene),poly(3-dodecylthiophene), poly(3-methoxythiophene),poly(3-ethoxythiophene), poly(3-octoxythiophene),poly(3-carboxylthiophene), poly(3-methyl-4-carboxylthiophene),poly(3,4-ethylenedioxythiophene), polyaniline, poly(2-methylaniline),poly(2-octylaniline), poly(2-isobutylaniline), poly(3-isobutylaniline),poly(2-anilinesulfonic acid), poly(3-anilinesulfonic acid), and thelike.

Any of the above-described conductive high molecules may be used aloneas a conductive composition to form a light-transmitting electrode.Alternatively, an organic resin can be added to any of theabove-described conductive high molecules in order to adjust filmcharacteristics such as film quality or intensity of alight-transmitting electrode formed of a conductive composition.

As an organic resin, a thermosetting resin, a thermoplastic resin, or aphotocurable resin which is compatible with a conductive high moleculeor can be mixed and dispersed into a conductive high molecule can beused. As examples of such a resin, the following can be given: apolyester-based resin such as polyethylene terephthalate, polybutyleneterephthalate, or polyethylene naphthalate; a polyimide-based resin suchas polyimide or polyamide imide; a polyamide resin such, as polyamide 6,polyamide 66, polyamide 12, or polyamide 11; a fluorine resin such aspoly(vinylidene fluoride), polyvinyl fluoride, polytetrafluoroethylene,ethylene tetrafluoroethylene copolymer, or polychlorotrifluoroethylene;a vinyl resin such as polyvinyl alcohol, polyvinyl ether, polyvinylbutyral, polyvinyl acetate, or polyvinyl chloride; an epoxy resin; axylene resin; an aramid resin; a polyurethane-based resin; apolyurea-based resin; a melamine resin; a phenol-based resin; polyether;an acrylic-based resin, or a copolymer of any of those resins.

Furthermore, in order to adjust electric conductivity of a conductivecomposition, the conductive composition may be doped with an acceptordopant or a donor dopant so that oxidation-reduction potential of aconjugated electron in a conjugated conductive high molecule may bechanged.

A halogen compound, a Lewis acid, a protonic acid, an organic cyanocompound, an organic metal compound, or the like can be used as anacceptor dopant. As examples of a halogen compound, there are chlorine,bromine, iodine, iodine chloride, iodine bromide, and iodine fluoride.As examples of a Lewis acid, there are phosphorus pentafluoride, arsenicpentafluoride, antimony pentafluoride, boron trifluoride, borontrichloride, and boron tribromide. As examples of a protonic acid, thereare an inorganic acid such as hydrochloric acid, sulfuric acid, nitricacid, phosphoric acid, fluoroboric acid, hydrofluoric acid, andperchloric acid; and an organic acid such as organic carboxylic acid andorganic sulfonic acid. As organic carboxylic acid and organic sulfonicacid, the above-described organic carboxylic acid compound and anorganic sulfonic acid compound can be used. As an organic cyanocompound, a compound having two or more cyano groups in a conjugatedbonding, for example, tetracyano ethylene, tetracyano ethylene oxide,tetracyanobenzene, tetracyanoquinodimethane, tetracyanoazanaphthalene,and the like are given.

As a donor dopant, alkali metal, alkaline earth metal, a quaternaryamine compound, or the like can be given.

Alternatively, a conductive composition is dissolved in water or anorganic solvent (e.g., an alcohol-based solvent, a ketone-based solvent,an ester-based solvent, a hydrocarbon-based solvent, an aromatic-basedsolvent) and a wet process is used, whereby a thin film which serves asa light-transmitting electrode layer can be formed.

There is no particular limitation on a solvent which dissolves aconductive composition. A solvent which dissolves the above-describedconductive high molecules and high molecular resin compounds such as anorganic resin may be used. For example, a conductive composition may bedissolved in any one or a mixture of water, methanol, ethanol, propylenecarbonate, N-methylpyrrolidone, dimethylformamide, dimethylacetamide,cyclohexanone, acetone, methyl ethyl ketone, methyl isobutyl ketone,toluene, or the like.

After a conductive composition is dissolved in a solvent as describedabove, a film thereof is formed over the insulating film 838 by a wetprocess such as an application method, a coating method, a dropletdischarge method (also referred to as an inkjet method), or a printingmethod, whereby the pixel electrode 840 can be obtained. The solvent maybe dried with heat treatment or may be dried under reduced pressure. Inthe case where an organic resin is a thermosetting resin, heat treatmentmay be performed. In the case where an organic resin is a photocurableresin, light irradiation treatment may be performed.

The partition film 842 can be formed in such a manner that an insulatingfilm is formed over the entire surface of the substrate by a CVD method,a sputtering method, an application method, or the like and then theinsulating film is selectively etched. Alternatively, the partition film842 can be formed selectively by a droplet discharge method, a printingmethod, or the like. Further alternatively, an insulating film is formedusing a positive photosensitive resin over the entire surface, and thenthe insulating film is exposed to light and developed, whereby thepartition film 842 having a desired shape can be formed.

As the organic compound-containing layer 844, at least a light-emittinglayer is formed, and a hole injecting layer, a hole transporting layer,an electron transporting layer, or an electron injecting layer may beformed as appropriate in addition to the light-emitting layer. Theorganic compound-containing layer 844 can be formed by an applicationmethod such as an ink jet method or an evaporation method.

Through the above-described steps, the light-emitting element 850 inwhich the organic compound-containing layer 844 including at least thelight-emitting layer is interposed between the pixel electrode 840 andthe counter electrode 846 can be obtained.

Next, a counter substrate 860 is provided so as to face the supportingsubstrate 120 (see FIG. 10B). A filler 858 may be provided between thecounter substrate 860 and the counter electrode 846, or a space betweenthe counter substrate 860 and the counter electrode 846 may be filledwith an inert gas. Note that a protective film may also be formed so asto cover the counter electrode 846.

Note that, in order to prevent desorption of halogen which terminatesdangling bonds in the semiconductor film 140, a temperature less thanthe temperature of the heat treatment for separating the semiconductorsubstrate is desirably used until the light-emitting element 850 isformed and sealed with the counter substrate 860. As described above,the temperature of the heat treatment for separating the semiconductorsubstrate is set as the highest temperature of the process and theprocessing temperatures of other steps are set to less than thetemperature of the heat treatment, whereby desorption of halogen whichterminates dangling bonds in the semiconductor film 140 can beprevented.

Through the above-described steps, the EL display device of thisembodiment mode is completed.

As for transistors included in the display device of this embodimentmode, the semiconductor film which forms the channel formation region isterminated by halogen and improvement of the electric characteristics isachieved. In addition, the insulating film containing silicon and oxygenas its composition in which halogen is contained and the insulating filmcontaining silicon and nitrogen as its composition each of which has ahigh gettering effect of metal impurities or a high blocking effectthereof is formed, and thus the display device with high reliability canbe manufactured. Moreover, the channel formation region can be formed ofa single-crystal semiconductor, and thus variation in transistorcharacteristics of each pixel can be reduced more, compared with thecase of a display device using a polycrystalline semiconductor for achannel formation region. Thus, display unevenness of a light-emittingdevice can be suppressed.

Note that there is no particular limitation on the transistors includedin the display device of this embodiment mode. For example, a transistorwhich have the structure described in Embodiment Mode 2 can also beemployed.

Note that this embodiment mode can be combined as appropriate with otherembodiment modes described in this specification.

Embodiment Mode 4

In this embodiment mode, an example of a semiconductor device to whichthe semiconductor device manufacturing substrate of the presentinvention is applied will be described.

FIG. 13 shows an example of a microprocessor 200 as an example of asemiconductor device. The microprocessor 200 is manufactured byapplication of the semiconductor device manufacturing substrate of theabove embodiment modes. This microprocessor 200 includes an arithmeticlogic unit (ALU) 201, an ALU controller 202, an instruction decoder 203,an interrupt controller 204, a timing controller 205, a register 206, aregister controller 207, a bus interface (Bus I/F) 208, a read-onlymemory 209, and a memory interface (ROM I/F) 210.

An instruction input to the microprocessor 200 through the bus interface208 is input to the instruction decoder 203, decoded therein, and theninput to the ALU controller 202, the interrupt controller 204, theregister controller 207, and the timing controller 205. The ALUcontroller 202, the interrupt controller 204, the register controller207, and the timing controller 205 conduct various controls based on thedecoded instruction. Specifically, the ALU controller 202 generatessignals for controlling the operation of the ALU 201. While themicroprocessor 200 is executing a program, the interrupt controller 204processes an interrupt request from an external input/output device or aperipheral circuit based on its priority or a mask state. The registercontroller 207 generates an address of the register 206, and reads andwrites data from and to the register 206 in accordance with the state ofthe microprocessor 200. The timing controller 205 generates signals forcontrolling timing of operation of the ALU 201, the ALU controller 202,the instruction decoder 203, the interrupt controller 204, and theregister controller 207. For example, the timing controller 205 isprovided with an internal clock generator for generating an internalclock signal CLK2 based on a reference clock signal CLK1, and suppliesthe clock signal CLK2 to the various above-described circuits. Note thatthe microprocessor 200 shown in FIG. 10 is only an example in which theconfiguration is simplified, and an actual microprocessor can havevarious configurations depending on the uses.

Improvement of electric characteristics of such a microprocessor 200 canbe achieved by application of the semiconductor device manufacturingsubstrate and the semiconductor device of the above embodiment modes,and an integrated circuit which has good characteristics can be formed.In addition, an integrated circuit can be formed using a single-crystalsemiconductor film, and thus higher performance, higher processingspeed, and the like can be realized.

Next, an example of a semiconductor device which has an arithmeticfunction that is capable of contactless data transmission and receptionis described with reference to FIG. 14. FIG. 14 shows an example of acomputer which operates to transmit and receive signals to and from anexternal device by wireless communication (such a computer ishereinafter referred to as an “RFCPU”). An RFCPU 211 has an analogcircuit portion 212 and a digital circuit portion 213. The analogcircuit portion 212 has a resonance circuit 214 with a resonancecapacitor, a rectifier circuit 215, a constant voltage circuit 216, areset circuit 217, an oscillator circuit 218, a demodulator circuit 219,and a modulator circuit 220. The digital circuit portion 213 has an RFinterface 221, a control register 222, a clock controller 223, aninterface 224, a central processing unit 225, a random-access memory226, and a read-only memory 227. The operation of the RFCPU 211 whichhas such a configuration is roughly as follows. The resonance circuit214 generates an induced electromotive force based on a signal receivedby an antenna 228. The induced electromotive force is stored in acapacitor portion 229 through the rectifier circuit 215. This capacitorportion 229 is preferably formed using a capacitor such as a ceramiccapacitor or an electric double layer capacitor. The capacitor portion229 does not need to be integrated with the RFCPU 211 and it isacceptable as long as the capacitor portion 229 is mounted as adifferent component on a substrate with an insulating surface which isincluded in the RFCPU 211.

The reset circuit 217 generates a signal for resetting and initializingthe digital circuit portion 213. For example, the reset circuit 217generates a signal which rises after rise in the power supply voltagewith delay as a reset signal. The oscillator circuit 218 changes thefrequency and duty ratio of a clock signal in response to a controlsignal generated by the constant voltage circuit 216. The demodulatorcircuit 219 formed using a low-pass filter binarizes the amplitude of,for example, a received amplitude-modulated (ASK) signal. The modulatorcircuit 220 varies the amplitude of an amplitude-modulated (ASK)transmission signal and transmits the signal. The modulator circuit 220changes the amplitude of a communication signal by changing a resonancepoint of the resonance circuit 214. The clock controller 223 generates acontrol signal for changing the frequency and duty ratio of a clocksignal in accordance with the power supply voltage or a consumptioncurrent of the central processing unit 225. The power supply voltage ismanaged by the power management circuit 230.

A signal input from the antenna 228 to the RFCPU 211 is demodulated bythe demodulator circuit 219 and then decomposed into a control command,data, and the like by the RF interface 221. The control command isstored in the control register 222. The control command includes readingof data stored in the read-only memory 227, writing of data to therandom-access memory 226, an arithmetic instruction to the centralprocessing unit 225, and the like. The central processing unit 225accesses the read-only memory 227, the random-access memory 226, and thecontrol register 222 via the interface 224. The interface 224 has afunction of generating an access signal for any of the read-only memory227, the random-access memory 226, and the control register 222 based onan address the central processing unit 225 requests.

As an arithmetic method of the central processing unit 225, a method maybe employed in which the read-only memory 227 stores an operating system(OS) and a program is read and executed at the time of startingoperation. Alternatively, a method may be employed in which a dedicatedarithmetic circuit is provided and arithmetic processing is conductedusing hardware. In a method in which both hardware and software areused, part of processing can be conducted by a dedicated arithmeticcircuit and the other part of the arithmetic processing can be conductedby the central processing unit 225 using a program.

Improvement of electric characteristics of such an RFCPU 211 can beachieved by application of the semiconductor device manufacturingsubstrate and the semiconductor device of the above embodiment modes,and an integrated circuit which has good characteristics can be formed.In addition, an integrated circuit can be formed using a single-crystalsemiconductor film, and thus higher performance, higher processingspeed, and the like can be realized. Note that, although FIG. 14 showsthe mode of the RFCPU, a device such as an IC tag is also possible aslong as it has a communication function, an arithmetic processingfunction, and a memory function.

The semiconductor device manufacturing substrate of the presentinvention can also be formed in such a manner that a large-size glasssubstrate called mother glass for manufacturing a display panel is usedas a supporting substrate and a semiconductor film is bonded to thelarge-size glass substrate. FIG. 15 shows the case where mother glass isused as a supporting substrate 120 and semiconductor films 140 arebonded to the supporting substrate 120. A plurality of display panels iscut out from the mother glass, and the semiconductor films 140 aredesirably bonded to match formation regions of display panels 522. Notethat the semiconductor films 140 are terminated by halogen, and halogenis desirably contained at a peak concentration of the range of 1×10¹⁷atoms/cm³ to 1×10²¹ atoms/cm³. Since the mother glass has a larger areathan a semiconductor substrate, it is desirable that a plurality ofsemiconductor films 140 be arranged within the formation regions of thedisplay panels 522, as shown in FIG. 15. This makes it possible toincrease the number of panels to be taken from the mother glass, andthus productivity is dramatically increased. Each of the display panels522 includes a scan line driver circuit region 523, a signal line drivercircuit region 524, and a pixel formation region 525. Each of thesemiconductor films 140 is bonded to the supporting substrate 120 sothat these regions are included in each of the display panels 522.

Note that a large-size glass substrate called mother glass containsmetal impurities such as sodium, which is a problem. However, as for thesemiconductor device manufacturing substrate of the present invention,an insulating film containing silicon and nitrogen as its compositionand an insulating film containing silicon and oxygen as its compositionin which halogen is contained each of which has a high blocking effectand a high gettering effect is formed between the glass substrate andthe semiconductor film. Thus, deterioration of characteristics of thedisplay panel or the like can be prevented, and increase in reliabilitycan be achieved.

FIGS. 16A and 16B show an example of a pixel of a liquid crystal displaydevice to which a semiconductor device manufacturing substrate of thepresent invention is applied and in which a transistor for a pixelportion is formed using a semiconductor film of the semiconductor devicemanufacturing substrate. FIG. 16A is a plane view of a pixel in which ascan line 526 intersects with the semiconductor film, and a signal line527 and a pixel electrode 528 are connected to each other. FIG. 16B is across-sectional view taken along the chained line J-K in FIG. 16A.

In FIG. 16B, there is a region which has a structure in which thesemiconductor film 140 is stacked over the supporting substrate 120 withthe bonding layer 114, the insulating film 106 containing silicon andnitrogen as its composition, and the third insulating film 107containing silicon and oxygen as its composition which are stacked inorder over the supporting substrate 120 interposed therebetween, and apixel transistor of this embodiment mode is formed to include theabove-describe region. In this embodiment mode, the semiconductor film140 is a single-crystal semiconductor film. In addition, thesemiconductor film 140 is terminated by halogen, and halogen isdesirably contained at a peak concentration of the range of 1×10¹⁷atoms/cm³ to 1×10²¹ atoms/cm³.

The pixel electrode 528 is provided over an interlayer insulating film518. A contact hole for connecting the semiconductor film 140 and thesignal line 527 is formed in the interlayer insulating film 518. Acolumnar spacer 531 is provided over the signal line 527 so as to fill astep due to the contact hole formed in the interlayer insulating film518. A counter substrate 529 is provided with a counter electrode 530. Aliquid crystal 532 held by an orientation film 545 and an orientationfilm 546 is provided in a space formed by the columnar spacer 531. Notethat, although not shown here, a polarization plate is provided outsidethe supporting substrate 120 or the counter substrate 529, if necessary.

The interlayer insulating film 518 can be formed as a single-layer filmor a stacked-layer film. Note that a planarization film which can smoothunevenness due to a structural body such as a transistor formed underthe interlayer insulating film 518 and can form an even surface isdesirably formed as the interlayer insulating film 518. For example, theinterlayer insulating film 518 can be formed using an organic materialsuch as polyimide, polyamide, polyvinyl phenol, benzocyclobutene,acrylic, or epoxy; a siloxane material such as a siloxane resin; anoxazole resin; or the like by an application method such as a spincoating method. Alternatively, a BPSG film may be formed as theinterlayer insulating film 518. Further alternatively, an insulatingfilm such as a silicon oxide film, a silicon nitride film, a siliconoxynitride film, or a silicon nitride oxide film can be formed by a CVDmethod or a sputtering method. Still alternatively, an insulating filmformed using an organic material and an insulating film formed using aninorganic material may be stacked.

In the case of a reflective liquid crystal display device, a reflectiveelectrode may be formed as the pixel electrode 528. Specifically, thepixel electrode 528 can be formed using a reflective conductivematerial, for example, a metal element such as tantalum, tungsten,titanium, molybdenum, aluminum, chromium, or silver, or an alloymaterial or a compound material containing the metal element. Note that,in the case where a reflective film is formed separately from the pixelelectrode 528, or in the case of a transmissive liquid crystal displaydevice, the pixel electrode 528 may be formed as a light-transmittingelectrode and formed using a light-transmitting conductive material. Asa light-transmitting conductive material, indium tin oxide (ITO), zincoxide (ZnO), indium zinc oxide (IZO), zinc oxide doped with gallium(GZO), or the like can be used.

The pixel electrode 528 can be formed using a conductive compositioncontaining a conductive high molecule (also referred to as a conductivepolymer). A thin film of the pixel electrode formed using a conductivecomposition desirably has a sheet resistance of less than or equal to10000 Ω/square and a light transmittance of less than or equal to 70% ata wavelength of 550 nm. In addition, the resistance of the conductivehigh molecule which is contained in the conductive composition isdesirably less than or equal to 0.1 Ω·cm. Note that a conductive highmolecule is described in detail according to the conductive highmolecule which can be used for the pixel electrode 840 or the counterelectrode 846 in Embodiment Mode 3.

The columnar spacer 531 can be obtained in such a manner that aninsulating film is formed over the entire surface of the substrate,using an organic material such as epoxy, polyimide, polyamide, polyimideamide, or acrylic, or an insulating material such as silicon oxide,silicon nitride, silicon oxynitride, or silicon nitride oxide and thenthe insulating film is etched into a desired shape.

A material for the orientation film 545 and the orientation film 546 maybe selected in accordance with an operation mode of a liquid crystalwhich is to be used, and a film which can align liquid crystals in acertain direction is formed. For example, a film is formed using amaterial such as polyimide or polyamide and orientation treatment isperformed on the film, whereby the film can function as an orientationfilm. Rubbing, irradiation with ultraviolet rays or the like, or thelike may be performed for the orientation treatment. Although there isno particular limitation on a formation method of the orientation film545 and the orientation film 546, various printing methods or a dropletdischarge method enables selective formation of the orientation film 545and the orientation film 546.

The liquid crystal 532 is formed using a desired liquid crystalmaterial. For example, the liquid crystal 532 can be formed in such amanner that a liquid crystal material is dropped within a frame-shapedseal pattern formed of a sealant. A liquid crystal material may bedropped by a dispenser method or a droplet discharge method. Note thatit is desirable that a liquid crystal material be deaerated underreduced pressure in advance, or be deaerated under reduced pressureafter a liquid crystal is dropped. Note that a liquid crystal materialis desirably dropped under an inert gas atmosphere so that impurities orthe like are not mixed. It is desirable that steps after the liquidcrystal 532 is formed by dropping of a liquid crystal material until thesupporting substrate 120 and the counter substrate 529 are bonded toeach other be performed under reduced pressure so that air bubbles orthe like are not formed in the liquid crystal 532. Alternatively, theliquid crystal 532 can be formed in such a manner that after thesupporting substrate 120 and the counter substrate 529 are bonded toeach other, a liquid crystal material is injected within a frame-shapedpattern formed of a sealant, by utilization of a capillary phenomenon.In that case, a portion which is to serve as an inlet of a liquidcrystal is formed in the sealant or the like in advance. Note that aliquid crystal material is desirably injected under reduced pressure.

As the counter substrate 529, for example, various glass substrates suchas an aluminosilicate glass substrate, an aluminoborosilicate glasssubstrate, or a barium borosilicate glass substrate; a quartz substrate;a ceramic substrate; a sapphire substrate; or the like can be used. Notethat, in the case of a reflective liquid crystal display device, alight-transmitting substrate (specifically, a glass substrate, a quartzsubstrate, or the like) is used as the counter substrate 529. Inaddition, in the case of a transmissive liquid crystal display device, anon-transmissive substrate (e.g., a ceramic substrate or a sapphiresubstrate) as well as a light-transmitting substrate can be used. Notethat the counter electrode 530 and the orientation film 546 may beformed over the counter substrate 529 before the counter substrate 529is bonded to the supporting substrate 120. Alternatively, the countersubstrate 529 may be provided with a color filter, a black matrix, orthe like.

FIG. 17A shows an example of an EL display device to which asemiconductor device manufacturing substrate of the present invention isapplied and in which a transistor for a pixel portion is formed using asemiconductor film of the semiconductor device manufacturing substrate.Note that a structure of the transistor of the EL display device differsfrom that of the display device described in Embodiment Mode 3. FIG. 17Ais a plane view of a pixel which includes a selection transistor 533connected to a signal line 527 and a display control transistor 534connected to a current supply line 535. This display device has astructure in which a light-emitting element including an organiccompound-containing layer as a light-emitting layer is provided for eachpixel. A pixel electrode 528 is connected to the display controltransistor 534. FIG. 17B is a cross-sectional view showing a main partof such a pixel.

In FIG. 17B, there is a region which has a structure in which thesemiconductor film. 140 is stacked over the supporting substrate 120with the bonding layer 114, the insulating film 106 containing siliconand nitrogen as its composition, and the third insulating film 107containing silicon and oxygen as its composition which are stacked inorder over the supporting substrate 120 interposed therebetween, and thedisplay control transistor 534 is formed to include such a region. Inthis embodiment mode, the semiconductor film 140 is a single-crystalsemiconductor film. In addition, the semiconductor film 140 isterminated by halogen, and halogen is desirably contained at a peakconcentration of the range of 1×10¹⁷ atoms/cm³ to 1×10²¹ atoms/cm³.Structures of the bonding layer 114, the insulating film 106 containingsilicon and nitrogen as its composition, the third insulating film 107containing silicon and oxygen as its composition, the semiconductor film140, the interlayer insulating film 518, and the like are the same asthose in FIG. 16B. A peripheral portion of the pixel electrode 528 issurrounded by an insulating partition film 536. An organiccompound-containing layer 537 including at least a light-emitting layeris formed over the pixel electrode 528. A counter electrode 530 isformed over the organic compound-containing layer 537. The pixel portionis filled with a sealing resin 538, and the counter substrate 529 isprovided as a reinforcing plate.

A display screen of the EL display device of this embodiment mode isformed in such a manner that such pixels are arranged in matrix. In thiscase, when a channel portion of the transistor of the pixel is formedusing the semiconductor film 140 which is a single-crystalsemiconductor, there are advantages in that characteristics do not varyamong transistors and unevenness is not generated in emission luminanceof each pixel. Thus, driving while controlling luminance of alight-emitting element with current becomes easy, and a correctioncircuit which corrects variations in characteristics of a transistor isnot needed, and thus load on a driver circuit can be reduced.Furthermore, a light-transmitting substrate can be selected as thesupporting substrate 120, and thus a bottom emission type EL displaydevice which emits light from the supporting substrate 120 side can beformed.

As described above, a single-crystal semiconductor film is also formedover mother glass used for manufacturing a liquid crystal display deviceor an EL display device, and a transistor can be formed using thesingle-crystal semiconductor film. A transistor formed using asingle-crystal semiconductor film is superior to an amorphous silicontransistor in all operating characteristics such as current drivecapacity, and thus the size of the transistor can be reduced.Accordingly, an aperture ratio of a pixel portion in a display panel canbe increased. In addition, a structure is employed in which a film whichhas a high blocking effect is provided between mother glass and asingle-crystal semiconductor film, and thus a display device with highreliability can be provided. Note that a microprocessor as describedwith reference to FIG. 13 and FIG. 14 can also be formed, and thus adisplay device can be equipped with a function of a computer. Moreover,a display which is capable of input and output of data without contactcan also be manufactured.

A variety of electronic devices can be formed using the semiconductordevice manufacturing substrate of the present invention. As examples ofelectronic devices, there are a camera such as a video camera or adigital camera, a navigation system, a sound reproducing device (a caraudio, an audio component, or the like), a computer, a game machine, aportable information terminal (a mobile computer, a cellular phone, amobile game machine, an electronic book, or the like), an imagereproducing device having a recording medium (specifically, a device forreproducing a recording medium such as a digital versatile disc (DVD)and having a display for displaying the reproduced image), and the like.

FIG. 18A shows an example of a cellular phone. A cellular phone 301described in this embodiment mode includes a display portion 302,operation switches 303, and the like. In the display portion 302, theliquid crystal display device described with reference to FIGS. 16A and16B or the EL display device described with reference to FIGS. 10A and10B or FIGS. 17A and 17B can be used. With use of the display device ofthis embodiment mode, a display portion with high image quality can beformed. In addition, the semiconductor device of the present inventioncan be also applied to a microprocessor or a memory which is included inthe cellular phone 301.

FIG. 18B shows a digital player 304, which is one of typical examples ofan audio device. The digital player 304 shown in FIG. 18B includes adisplay portion 302, operation switches 303, earphones 305, and thelike. Instead of the earphones 305, headphones or wireless earphones canbe used. In the digital player 304, the semiconductor device of thepresent invention can be applied to a memory portion which stores musicinformation or a microprocessor which operates the digital player 304.The digital player 304 having this structure can achieve reduction insize and weight. By application of the liquid crystal display devicedescribed with reference to FIGS. 16A and 16B or the EL display devicedescribed with reference to FIGS. 10A and 10B or FIGS. 17A and 17B tothe display portion 302, the display portion 302 can display an image ortextual information with high definition even if it has a screen size ofabout 0.3 inches to 2 inches.

FIG. 18C shows an electronic book 306. This electronic book 306 includesa display portion 302 and operation switches 303. A modem may be builtin, or a structure in which information can be transmitted and receivedwirelessly may be employed. In the electronic book 306, thesemiconductor device of the present invention can be used for a memoryportion which stores information or a microprocessor which operates theelectronic book 306. In the memory portion, a NOR-type nonvolatilememory with a memory capacity of greater than or equal to 20 gigabytes(GB) and less than or equal to 200 gigabytes (GB) can be used, withwhich images or sounds (music) can be stored and reproduced. Byapplication of the liquid crystal display device described withreference to FIGS. 16A and 16B or the EL display device described withreference to FIGS. 10A and 10B or FIGS. 17A and 17B to the displayportion 302, the display portion 302 can perform display with high imagequality.

Note that this embodiment mode can be combined as appropriate with otherembodiment modes described in this specification.

This application is based on Japanese Patent Application serial no.2007-162106 filed with Japan Patent Office on Jun. 20, 2007, the entirecontents of which are hereby incorporated by reference.

What is claimed is:
 1. A semiconductor substrate comprising: asingle-crystal semiconductor film containing halogen; a first insulatingfilm overlapped with the single-crystal semiconductor film, the firstinsulating film comprising silicon and oxygen as its composition andcontaining halogen; a second insulating film overlapped with the firstinsulating film, the second insulating film comprising silicon andnitrogen as its composition; a first bonding layer overlapped with thesecond insulating film, the first bonding layer having siloxane bonds; abarrier film overlapped with the first bonding layer, the barrier filmcomprising one selected from the group consisting of a stacked film of asilicon nitride film and a silicon oxide film, a stacked film of asilicon nitride film and a silicon oxynitride film, a stacked film of asilicon nitride oxide film and a silicon oxide film and a stacked filmof a silicon nitride oxide film and a silicon oxynitride film; and asupporting substrate overlapped with the barrier film, wherein danglingbonds of the single-crystal semiconductor film at an interface betweenthe single-crystal semiconductor film and the first insulating film areterminated by halogen diffused from the first insulating film.
 2. Thesemiconductor substrate according to claim 1, wherein the firstinsulating film is a thermal oxide film.
 3. The semiconductor substrateaccording to claim 1, wherein the first insulating film is a siliconoxide film or a silicon oxynitride film.
 4. The semiconductor substrateaccording to claim 1, wherein the second insulating film is a siliconnitride film or a silicon nitride oxide film.
 5. The semiconductorsubstrate according to claim 1, wherein the halogen is fluorine orchlorine.
 6. The semiconductor substrate according to claim 1, whereinthe supporting substrate is one selected from the group consisting of aglass substrate, a quartz substrate, a ceramic substrate, a sapphiresubstrate, and a metal substrate whose surface is coated with aninsulating film.
 7. The semiconductor substrate according to claim 1,wherein a second bonding layer is provided between the barrier film andthe first bonding layer.
 8. A semiconductor device comprising: a barrierfilm over a substrate, the barrier film comprising one selected from thegroup consisting of a stacked film of a silicon nitride film and asilicon oxide film, a stacked film of a silicon nitride film and asilicon oxynitride film, a stacked film of a silicon nitride oxide filmand a silicon oxide film and a stacked film of a silicon nitride oxidefilm and a silicon oxynitride film; a first bonding layer over thebarrier film, the first bonding layer having siloxane bonds; a firstinsulating film over the first bonding layer a substrate, the firstinsulating film comprising silicon and nitrogen as its composition; asecond insulating film over the first insulating film, the secondinsulating film comprising silicon and oxygen as its composition andcontaining halogen; a single-crystal semiconductor film over the secondinsulating film, the single-crystal semiconductor film containinghalogen; a third insulating film over the single-crystal semiconductorfilm; and a gate electrode over the third insulating film, the gateelectrode overlapping with the single-crystal semiconductor film,wherein dangling bonds of the single-crystal semiconductor film at aninterface between the single-crystal semiconductor film and the secondinsulating film are terminated by halogen diffused from the secondinsulating film.
 9. The semiconductor device according to claim 8,wherein the second insulating film is a thermal oxide film.
 10. Thesemiconductor device according to claim 8, wherein the second insulatingfilm is a silicon oxide film or a silicon oxynitride film.
 11. Thesemiconductor device according to claim 8, wherein the first insulatingfilm is a silicon nitride film or a silicon nitride oxide film.
 12. Thesemiconductor device according to claim 8, wherein the halogen isfluorine or chlorine.
 13. The semiconductor device according to claim 8,wherein the substrate is one selected from the group consisting of aglass substrate, a quartz substrate, a ceramic substrate, a sapphiresubstrate, and a metal substrate whose surface is coated with aninsulating film.
 14. The semiconductor device according to claim 8,further comprising a second bonding layer, wherein the second bondinglayer is provided between the barrier film and the first bonding layer.